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ESSENTIALS  OF 
OPERATIVE  DENTISTRY 


Digitized  by  the  Internet  Archive 

in  2010  with  funding  from 

Open  Knowledge  Commons 


http://www.archive.org/details/essentialsofoperOOdavi 


ESSENTIALS  OF 


OPEEATIVE  DENTISTRY 


BY 

W.  CLYDE  DAVIS,  M.D.,  D.D.S. 

DEAN  AND  PROFESSOR  OF  OPERATIVE  DENTISTRY  AND  TECHNIC,  LINCOLN  DENTAL 
COLLEGE,    LINCOLN,    NEBRASKA. 


SECOND  REVISED  EDITION 


ST.  LOUIS 

C.  V.  MOSBY  COMPANY 
1916 


'  0    !   f 


Copyright,  1916,  by  C.  V.  Mosby  Company 


Press  of 

C.  V.  Mosby  Company 

St.  Louis 


PREFACE  TO  SECOND  EDITION. 

Ill  presenting  the  second  edition  of  this  work,  it  is  the  aim 
of  the  author  to  follow  the  plan  of  the  first  edition,  in  that  it  be 
concise  and  vet  cover  a  wide  field  in  operative  dentistry. 

The  book  has  been  thoroughly  rewritten  and  extensively  illus- 
trated. Four  new  chapters  have  been  added,  several  have  been 
materially  enlarged,  and  others  eliminated  entirely  in  this  edition. 

There  is  a  complete  rearrangement  of  the  chapters  which  it  is 
believed  will  more  nearly  coincide  with  the  progress  of  the  stu- 
dent through  his  technical  work  and  the  operatory. 

W.  C.  D. 


PREFACE  TO  FIRST  EDITION. 

In  the  preparation  of  this  text-book  it  has  been  the  author's 
aim  to  meet  a  demand  in  dental  college  work  for  a  treatise  on 
operative  dentistry  which  is  sufficiently  condensed  to  enable  the 
student  to  master  its  contents  in  the  comparatively  short  college 
terms  at  his  disposal. 

The  subject  matter  selected  is  that  w^hich  is  generally  taught 
by  the  instructors  styled  as  "Professor  of  Operative  Dentistry." 

From  a  study  of  these  teachers'  courses  of  instruction  it  would 
seem  that  the  definition  of  Operative  Dentistry  as  commonly  used 
today  would  be  "That  branch  of  dentistry  which  treats  of  the 
mechanical  procedures  performed  within  the  oral  cavity  looking 
to  the  salvage  of  the  teeth." 

However,  it  has  seemed  wise  in  several  instances  to  go  beyond 
the  exact  limitations  of  this  definition  to  get  a  better  correlation 
of  subjects. 

The  arrangement  of  the  subject  matter  is  different  from  that 
usually  found,  but  is  in  accordance  with  the  usual  line  of  progress 
of  dental  students. 

The  author  claims  little  originality  in  the  essentials  presented, 
having  gleaned  the  facts  from  the  writings,  teachings  and  utter- 
ances of  our  greatest  educators. 

The  "quiz-explanation"  method  of  teaching  is  the  one  most  in 
vogue  in  the  leading  universities  as  productive  of  the  most  work 
on  the  part  of  the  classes  taught,  and  at  the  same  time  giving 
the  tutor  more  freedom  for  the  expression  of  opinions  to  give 
individuality  to  his   course   of  instruction. 

An  effort  has  been  made  to  so  publish  the  "Essentials  of  Oper- 
ative Dentistry"  that  it  would  serve  as  a  foundation  for  this  quiz 
course  as  well  as  be  suggestive  to  the  teacher  for  a  more  full 
explanation,  and,  at  the  same  time,  encourage  the  student  to  ex- 
tend his  studies  to  more  voluminous  reference  books,  when  time 
would  permit,  for  an  explanation  in   greater  detail. 

The  author  is  much  indebted  to  his  co-laborer,  partner  and  wife, 
Mattie  M.  Davis,  D.M.D.,  for  valuable  assistance  in  connection 
with  the  publication  of  this  volume. 

W.  C.  D. 


CONTENTS 

PART  I. 

CHAPTER  I.  Page 

Instrument  Nomenclature 17 

CHAPTPJR  II. 
Cavity  Nomenclature 21 

CHAPTER  III. 
Cavity  Preparation.     (General  Considerations.) 29 

CHAPTER  IV. 
Gaining   Access 31 

CHAPTER  V. 
Outline  Form 34 

CHAPTER  VI. 
Resistance  Form 38 

CHAPTER  VII. 
Retention  Form 40 

CHAPTER  VIII. 
Convenience  Form 42 

CHAPTER  IX. 
Removal  of  Remaining  Carious  Dentine. — Finishing  Enamel  Walls. — 

Toilet  of  the  Cavity 44 

CHAPTER  X. 
Management  of  Pit  and  Fissure  Cavities.     (Class  One.) 48 

CHAPTER  XI. 
Management  of  Pit  and  Fissure  Cavities.    (Class  One,  Concluded.)     .     .      52 

CHAPTER  XII. 
Management  of  Proximal  Cavities  i\   liicusJMus  and  Molars.     (Class 

Two.) 58 

CJIAPTER  XIII. 

Eargk   i'Roxi.MAL  Cavitiks   Exuangioking   tmk   Pulp.      (Class   Two,  Con- 
tinued.;      65 

y 


10  CONTENTS 

CHAPTER  XIV.  Page 

Management  of  Proximal  Cavities  in  Incisors  and  Cuspids  Not  Involv- 
ing THE  Angle,    (Class  Three.) 72 

CHAPTER  XV. 

Management  of  Proximal  Cavities  in  Incisors  Involving  the  Angle. 

(Class  Four.) 78 

CHAPTER  XVI. 

Management  of  Cavities  in  the  Gingival  Third.    (Class  Five.)     ....      93 

CHAPTER  XVII. 

Management  of  Abraded  Surfaces.    Occlusal  and  Incisal.     (Class  Six.)       96 

CHAPTER  XVIII. 
Cavity  Preparation  for  Gold  Inlays 98 


PART  11. 

CHAPTER  XIX. 
The  Making  and  Setting  of  a  Gold  Inlay 112 

CHAPTER  XX. 

Manipulation  of  Cohesive  Gold  in  the  Making  of  a  Filling 123 

CHAPTER  XXI. 

■  Manipulation  of  Cohesive  Gold  in  the  Making  of  Fillings  by  Classes     .     129 

CHAPTER  XXII. 
Finishing  Gold  Fillings 137 

CHAPTER  XXIII. 

Manipulation  of  Amalgam  in  the  Making  of  a  Filling 139 

CHAPTER  XXIV. 
The  Use  of  Cements  in  Filling  Teeth 146 

CHAPTER  XXV. 

Manipulation  op  Silicate  in  the  Making  op  a  Filling 148 

CHAPTER  XXVI. 
The  Use  op  Gutta-Percha  in  Filling  Teeth 164 

CHAPTER  XXVII. 
Tin  as  a  Filling  Material 166 

CHAPTER  XXVIII. 
Combination  Fillings 169 


CONTEXTS  11 

PART  III. 

CHAPTER  XXIX.  Page 

EXAMINATIOX  OF  THE  MOUTH  LOOKING  TO  DEXTAL   SERVICES 174 

CHAPTER  XXX. 
The  Alleviation  of  Dental  Pains 177 

CHAPTER  XXXI. 
Prophylactic  Treatment  of  the  Mouth 180 

CHAPTER  XXXII. 
Exclusion  of  Moisture 187 

CHAPTER  XXXIII. 
Treatment  of  Hypersensitive  Dentine 195 

CHAPTER  XXXIV. 
Protection  of  the  Vital  Pulp 204 

CHAPTER  XXXV. 
Pulp  Devitalization  and  Removal 211 

CHAPTER  XXXVI. 
Management  of  Putrescent  Pulp  Canals 219 

CHAPTER  XXXVII. 
The  Filling  of  Pulp  Canals 225 

CHAPTER  XXXVIII. 
Management  of  Children's  Teeth 229 

CHAPTER  XXXIX. 
Extraction  of  Permanent  Teeth 233 

CHAPTER  XL. 
Extraction  of  Temporary  Teeth 269 

CHAPTER  XLL 
Local  and  Regional  Anesthesia 275 

CHAI'TKR  XLIL 
The  i;se  of  Fused  Porcelai.v  i.v  Fijj,ing  Teeth 293 

CHAPTER  XLIII. 
Preparation  of  Cavities  for  Porcelain  I.vlays 29G 

CIIAI'TER  XLIV. 
The  Constbuctio.v  a.nd  I'LAcixr;  ok  a  Porcelain  Inla.y 300 


ILLUSTRATIONS 


FIG.  PAGE 

1.  Defects  in  enamel 21 

2.  Defects  in  enamel 22 

3.  Smooth  surface  decay 23 

4.  Smooth  surface  decay 23 

5.  Class  One  cavities  tilled 24 

6.  Class  Two   cavity  tilled 24 

7.  Class  Three   cavity  filled       25 

8.  Class  Four  cavity  filled 25 

9.  Class  Five  cavity  filled 25 

10.  Bisected  molar  in  which  a  mesial  Class  Two  cavity  has  been  cut  and  line 

angles  indicated 26 

11.  Bisected  molar  in  which  a  mesial  Class  Two  cavity  has  been  cut  and  point 

angles  indicated 26 

12.  Diagram  of  tooth,  giving  angles  and  surfaces 27 

13.  Technic  group  illustrating  outline  form 35 

14.  Another  view  of  cavities  illustrated  in  Fig.   13 35 

15.  Fillings  in  place  in  cavities  shown  in  Figs.  13  and  14 36 

16.  Another  view  of  fillings  shown  in  Fig.   15 36 

17.  Complex   Class    One    cavity   prepared 50 

18.  Class  One  filled.     Cavity  shown  in  Fig.  17 51 

19.  Large  Class  One  cavities  prepared 53 

20.  Class  One  filled.     Cavities  shown  in  Fig.  19 54 

21.  Lingual    pit    cavities 55 

22.  Class  One  filled.    Cavities  shown  in  Fig.  21 56 

23.  One  of  the  few  eases  in  which  the  step  may  be  omitted  in  Class  Two 

cavities 60 

24.  Class  Two  cavities  in  molar  and  bicuspid  suitable  for  cohesive  gold  or 

amalgam        61 

25.  Class  Two  filled.    Cavities  shown  in  Fig.  24 62 

26.  Fillings  shown  in  Fig.  25  contacted,  illustrating  the  marble  contact     .     .  63 

27.  Large  Class  Two  cavities  in  non-vital  teeth  restoring  part  of  the  occlusal 

surface  for  the  protection  of  weakened  walls 67 

28.  Class  Two  filled.     Cavities  shown  in  Fig.  27 67 

29.  Mesio-occluso-distal  cavities  in  molar  and  bicuspid,  vital  teeth     ....  68 

30.  Mesio-occluso-distal  fillings.     Cavities  shown  in  Fig.  29 68 

31.  (A)      First  superior  molar,  non- vital,  restoring  the  lingual  cusps.      (B) 

Second    superior    bicuspid,    non-vital,    restoring   the    entire    occlusal 

surface 69 

32.  Class  Two  filled.     Cavities  shown  in  Fig.   31 69 

33.  Class  Three  cavities  filled 73 

34.  Drawing  to  illustrate  the  retention  at  the  incisal  angle  of  Class   Three 

cavity 75 

35.  Class  Three  cavities  prepared  for  cohesive  gold 76 

36.  Class  Three  filled.     Cavities  shown  in  Fig.  35 76 

37.  Drawings  to  illustrate  the  principle  of  the  lever  in  the  dislodgement  of 

fillings  of  the  Fourth  Class,  plan  one 79 

38.  Drawings  to  illustrate  the  principle  of  the  lever  in  the  dislodgement  of 

fillings  of  the  Fourth  Class,  plans  one  and  two 80 

39.  Drawing   to   illustrate  the   difference   in   the   directions   the   point   angle 

fillings  take  in  tipping  to  exit  with  various  fillings 82 

12 


ILLUSTRATIONS  13 

FIG.  PAGE 

40.  Drawings  to  illustrate  the  importance  which  should  be  given  to  the  proper 

placing  of  the  incisal  point  angle  in  fillings  of  Class  Four,  plan  two  83 

41.  A  study  iu  the  proper  placing  and  depth  of  the  gingival  angles     ...  84 

42.  A  study  of  the  planes  in  which  the  gingival  angles  should  be  laid     .     .  84 

43.  Cavity  of  Class  Four,  plan  one,  for  cohesive  gold 85 

44.  Class   Four,   plan    cue,   cavity   filled 85 

45.  Shows  incisal  outline  in  Class  Four,  plan  one,  fillings  with  direct  occlusion  86 

46.  Cavity  of  Class  Four,  plan  two,  for  cohesive  gold 88 

47.  Class  Four,  plan  two,  filled 88 

48.  Cavity  of  Class  Four,  plan  three,  for  cohesive  gold 89 

49.  Class    Four,    plan    three,    filled 89 

50.  Cavity  of  Class  Four,  plan  four,  for  cohesive  gold 91 

51.  Class  Four,  plan  four,  filled 91 

52.  Cavity  of  Class  Four,  modified  plan  three,  for  cohesive  gold  in  the  distal 

of  the  superior  cuspid 92 

53.  Class  Four,  modified  plan  three,  filled 92 

54.  Cavities  Class  Five  for  cohesive  gold  or  amalgam 93 

55.  Class   Five   filled 94 

56.  Cavities   of  Class  One  for   gold  inlays 101 

57.  Class  One  inlay  in  position  showing  gold  wire  cast  iu  tlic  filling     .     .     .  102 

58.  Cavities  of  Class  Two  for  gold  inlays 103 

59.  Cavity  of  Class  Three  for  gold  inlay,  lingual  approach 105 

60.  Inlay  shown  in  Fig.  59  partly  in  place 105 

61.  Cavity  of  Class  Four,  plan  one,  for  gold  inlay 106 

62.  Class  Four,  plan  one,  inlay  in  position 106 

63.  Cavity  of  Class  Four,  plan  two,  for  gold  inlay 107 

64.  Class  Four,  plan  two,  gold  inlay  in  position 107 

65.  Cavity  of  Class  Four,  plan  three,  for  gold  inlay 108 

66.  Class  Four,  plan  three,  inlay  in  position 108 

67.  Cavity  of  Class  Four,  plan  four,  for  gold  inlay 109 

68.  Class  Four,  plan  four,  showing  cavity  side  of  pattern  with  pins     .     .     .  109 

69.  Class  Four,  plan  four,  inlay  in  position  before  removing  wire  loop     .     .  109 

70.  Cla.ss  Five  cavity  and  inlay 110 

71.  >Siiows  the  necessary  amount  of  metal  for  adecjuate  protection  of  abraded 

surfaces,    when    opening   the    bite 110 

72.  Largo   restoration   in   non-vital   ease 113 

7.'i.  Home  of  the  methods  by  which  inlays  may  be  given  retentive  form  in 

large   decays   and   non-vital    cases 115 

74.  Starting  cohesive  gold,  first  plan 130 

75.  Starting  cohesive   gold,   second   plan 131 

76.  Starting   cohesive    gold,    thii'd    plan 132 

77.  Burnishing  back  excess  golil   foil   in  covering  the  gingival  maigin     .     .  133 

78.  Covering   tlie   giiigivo-lingual   angle  with   cohesive   gold 134 

79.  Suitable  cavities  for  the  use  of  silicate  fillings 149 

80.  A  Class  One  cavity  on  the  labial  of  a  central  incisor  properly  prepared 

for  a  silicate  filling 149 

81.  Extensive  Class  Tliree  cavity  ])iit\H'i]y  prepared  for  a  silicate  filling     .     .  150 

82.  A  Class  Five  and  a  Class  Three  cavity  suitable  for  the  use  of  silicate 

as   a   filling ." 150 

83.  A  Class  Five  cavity  jtrojterly  (irepared  for  a  silicate  filling 151 

84.  A  Class  Three  cavity,  lingual  af»itroacli,  properly  preparcnl  for  a  silicate 

filling       ..." 151 

85.  A  small  Class   Three   cavity,   laiiial    approach,   properly   piepared   for  a 

silicate    filling 152 


14  ILLUSTRATIONS 

FIG.  I'^GE 

86.  A  small  Glass  Three  cavity,  lingual  approach,  properly  prepared  for  a 

silicate   filling 152 

87.  A  large  Class  Three  cavity,  labial  approach,  properly  prepared  for  a 

silicate  filling •  152 

88.  A  large  Class  Three  cavity,  lingual  approach,  properly  prepared  for  a 

silicate   filling 15-j 

89.  A  large  Class  Three  cavity  properly  prepared  for  a  silicate  filling     .     .  153 

90.  Two   extensive   Class   Three   cavities  properly   prepared   for   a   silicate 

filling 153 

91.  A  small  set  of  instruments  for  manipulating  silicate 154 

92.  A  suitable  slab  and  spatula  for  working  silicate 155 

93.  Proper  position  of  the  spatula  on  the  slab  w^hen  manipulating  silicate  156 

94.  Proper  placing  of  the  materials  when  manipulating  silicate     ....  156 

95.  Mixing  the   silicate  filling 157 

96.  Mixing  the   silicate  filling 157 

97.  Circular  motion  used  in  mixing  the  silicate  filling 158 

98.  Scraping  the  material  from  the  slab 159 

99.  The   entire   mix   on   the   spatula .  160 

100.  Method  of  removing  the  mix  from  the  spatula  to  the  slab 160 

101.  Proper  consistency  of  silicate 161 

102.  Shows  mix   of   silicate   too   thin 161 

103.  A   homemade   mallet    and   point 162 

104.  Three  cavities  suitable  for   silicate   fillings 163 

105.  Shows  the  results  obtained  after  filling  with  silicate  the  cavities  shown 

in  Fig.  104 163 

106.  Combination  gold  inlay  and  silicate 171 

107.  Amalgam  in  position  ready  to  receive  a  partial  facing  of  silicate     .     .  172 

108.  Amalgam  filling  shown  in  Fig.  107  with  the  silicate  facing  built  in     .  172 

109.  An  improper  position  with  the  operator  doing  his  work  at  arm's  length  235 

110.  Types  of  superior  central  incisors 236 

111.  Types   of   superior   lateral   incisors 237 

112.  Position  for  extracting  superior  incisors 238 

113.  Types  of  inferior  central  and  lateral  incisors 239 

114.  Position  for  extracting  lower  incisors 240 

115.  Types  of   superior  cuspids 241 

116.  Position  for  extracting  right  superior  cuspids 242 

117.  Position  for   extracting  left   superior  cuspids 243 

118.  Mesial   and  distal   application   of   forceps  to   a   superior  right   cuspid 

when  both  adjacent  teeth  have  been  extracted 244 

119.  Types   of   inferior   cuspids 246 

120.  Position  for  extracting  inferior  cuspids 247 

121.  Types  of  superior  first  and  second  bicuspids 248 

122.  Position  for  extracting  right  superior  bicuspids 249 

123.  Position  for  extracting  left  superior  bicuspids 250 

124.  Types   of  inferior   first   and   second  bicuspids 251 

125.  Position  for   extracting  right  inferior  bicuspids 252 

126.  Position  for  extracting  left  inferior  bicuspids 253 

127.  Types  of  superior  first  and  second  molars 254 

128.  Position  for  extracting  first  and  second  right  superior  molars     .     .     .  255 

129.  Position  for  extracting  first  and  second  left  superior  molars     .     .     .  256 

130.  Types  of  inferior  first   and  second  molars 257 

131.  Position  for  extracting  first  and  second  right  inferior  molars     .     .     .  258 

132.  Position  for  extracting  first  and  second  left  inferior  molars     ....  259 

133.  Types  of  superior  third  molars 260 


ILLUSTRATIONS  15 

FIG.  PAGE 

134.  T^-pes   of   abnormal   superior   third   molars 261 

135.  One  of   the  many   abnormal  conditions   found   M-hen   extracting  upper 

second    and    third   molars 262 

136.  Position  for  extracting  riglit  upper  third  molars 263 

137.  Position  for  extracting  upper  left  third   molars 264 

138.  T^-pes   of   inferior   third   molars 265 

139.  Elevator  beaked  forceps  for  extracting  third  molars 266 

140.  Position  for  extracting  right  inferior  third  molars 266 

141.  Position  for  extracting  left  inferior  third  molar 267 

142.  Complete  set  of  deciduous  teeth  with  the  first  permanent  molar  added     .  270 

143.  Irregularity  resulting  from  premature  extraction  of  first  deciduous  molar  271 

144.  Horizontal   injection 275 

145.  Perpendicular    injection 276 

146.  Drawing  representing  the  positions  of  needles  in  local  anesthesia     .     ,  277 

147.  First  position  in  the  mandibular  injection 278 

148.  Second   position   in   the   mandibular   injection 279 

149.  Third  position  for  the  mandibular  injection 280 

150.  Fourth  and  last  position  for  the  mandibular  injection 281 

151.  A  very  clear  and  easy  case  with  the  needle  in  the  best  position  for  the 

mandibular  injection 282 

152.  A  difficult  case  where  the  lingula  is  almost  entirely  wanting     ....  283 

153.  Same  mandible  as  shown  in  Fig.  153  with  the  needle  passed  to  position 

suflEiciently  high   to   be   above   the   lingula 284 

154.  A  mandible  which  belongs  to  a  class  on  which  it  is  very  hard  to  give 

a     mandibular     injection 285 

155.  First  and  ideal  position  for  giving  the  mental  injection 286 

156.  Second  position  for  giving  the  mental  injection 287 

157.  Position  of  needle  in  giving  the  infra-orbital  injection 289 

158.  Final  position  of  the  needle  in  giving  the  zygomatic  injection     .     .     .  291 

159.  Cavity  preparation  for  a  Class  Two  porcelain  inlay 297 

160.  A  Class  Three  cavity  labial  approach  for  porcelain  inlay 298 

161.  A  Class  Three  cavity  labial  approach  for  porcelain  inlay 298 

162.  A  Class  Three  cavity  lingual  approach  for  porcelain  inlay 299 

163.  A  Class  Four  cavity  incisal  approach  for  porcelain  inlay 300 

164.  A  Class  Four,  plan  one,  inciso-proximal  api>roach  for  porcelain  inlay  300 

165.  A  Class  Four,  plan  two,  with  doultle  step  for  porcelain  inlay     ....  301 

166.  A  Cla.ss  Four,  plan  three,  for  porcelain  inlay 302 

167.  Class   Five   cavities   for   porcelain    inlay 303 

168.  Incisal   cavity    for   porcelain    inlay 304 

169.  A  Class  Six  cavity  using  pin  anchorage  for  porcelain  inlay     ....  305 

170.  Chisels    for    securing    outline    form 314 

171.  Spoons    for    removing    softened    dentine 315 

172.  Enamel  hatchets   for   completing   outline   form   and  flattening  dentine 

walls 316 

173.  Instruments  for  cutting  point  angles  and  sharpening  base  line  angles     .  317 

174.  Hatchets  and  hoes  for  cutting  ascending   line  angles  and  completing 

retention  form 318 

175.  Gingival  marginal  trimmers 319 

176.  Gold   building   pluggers 320 

177.  Dr.  Rathbun  's  dentech  with  teeth  in  position  ready  for  practice  work  321 

178.  A  studr-nt  who  has  kept  his  appointment  with  his  patient,  "Mr.  Den- 

tech"        322 

179.  Forceps  made  after  tlx;  i)atterns  of  the  author 323 

180.  Forceps  made  after  the  patterns  of  the  author 324 


0PEEAT1\  E  13ENT1STEY 


PART  I 

CHAPTER  I. 
INSTRUMENT  NO:\IENCLATURE. 

A  dental  instrument  is  an  appliance,  or  tool,  by  means  of  ^vhicli 
a  dentist  performs  dental  operations.  It  is  quite  essential  that  we 
loarn  the  names  and  uses  of  the  instruments  most  in  use  if  we  are 
to  understand  the  teachno'  of  operative  procedures. 

Instruments  are  named  according  to  the  purpose  for  which  they 
are  intended,  where  and  how  used,  by  describing  their  working 
points  and  the  shape  of  their  shank. 

An  order  name  describes  that  for  which  an  instrument  is  used, 
as  for  example,  excavator,  clamps,  mallet,  pluggers,  burnishers,  etc. 

A  sub-order  name  describes  where  or  how  an  instrument  of  a 
given  order  is  used  and  is  made  by  inserting  a  prefix  before  the  or- 
der name.     P>xainples  are  hand  pluggers,  push  or  pull  scalers,  etc. 

A  class  name  describes  the  working  point  of  an  instrument.  Ex- 
amples are  serrated  plugger,  ball  burnisher,  chisel,  hatchet,  etc. 

A  sub-class  name  (k'sci-ibes  the  shai)e  of  the  shank,  and  is  made 
by  prefixing  this  (lcs('i-ii)tion  to  the  class  or  order  name  or  to  both 
combined.  P^xamples  are  bayonet  plugger,  bin-angle  chisel,  mon- 
angle  liatfhet  excavator,  etc. 

Rights  and  lefts  are  made  as  further  divisions  of  many  of  the 
sulvclasscs  of  instruments  and  this  division  is  especially  advan- 
tageous ill  the  spoons,  ])in-angle,  conti-a-angle  hatchets  and  mar- 
ginal trimmers,  as  it  enables  the  user  to  do  the  Avork  by  a  move- 
ment of  the  instrument  from  right  to  left,  or  left  to  right,  respec- 
tively. 

An  excavator  is  that  order  of  hand  instrument  used  in  the  re- 
iMoval  of  I00II1  substance  preparatoi-y  to  the  making  of  a  filling. 

A  chisel  is  thai  class  of  exeavatoi-  which  lias  Hu-  cutting  edge 
placed  at    right    angles  to   the  sliaft,   is  sharpciuMl  b\-   grinding  on 


]8  OPERATIVE    DENTISTRY 

one  side  only  and  is  used  by  a  pushing  force  applied  in  the  direc- 
tion of  the  long  axis  of  the  shaft. 

The  chisel  edg"e  is  made  with  a  bevel  at  an  angle  calculated  to 
plane  and  cleave  a  substance  possessed  of  a  grain,  and  is  so  tem- 
pered as  to  retain  an  edge  when  working  on  hard  substances. 

The  use  of  the  chisel  is,  therefore,  the  cleaving  and  planing  of 
enamel.  The  planing  of  dentine  may  be  done  with  a  chisel  or  with 
other  instruments  of  a  similar  edge. 

Chisels  are  divided  into  sub-classes  according  to  the  shapes  of 
their  shanks,  as  straight,  bin-angle,  contra-angle,  etc. 

A  hoe  is  that  class  of  excavator  with  the  cutting  edge  at  a  right 
angle  with  the  shaft,  sharpened  on  the  distal  side  only  and  is  used 
by  a  pulling  force  applied  parallel  with  the  long  axis  of  the  shaft. 

Hoes  are  divided  into  sub-classes  according  to  the  shape  of  their 
shanks,  as,  mon-angie,  bin-angle,  contra-angle  and  triple-angle  con- 
tra-angle.    The  hoe  is  used  mostly  for  cutting  dentine. 

A  hatchet  is  that  class  of  excavator  with  the  line  of  the  cutting 
edge  laid  in  the  plane  parallel  with  the  long  axis  of  the  shaft. 

Hatchets  are  divided  into  sub-classes  the  same  as  the  hoes,  ac- 
cording to  the  shape  of  their  shank,  as,  mon-angle,  bin-angle  and 
triple-angle  contra-angle.  The  hatchet  form  is  indispensable  for  the 
construction  of  flat  walls  and  internal  surfaces,  the  straightening 
of  lines  and  the  sharpening  of  angles. 

A  gingival  marginal  trimmer  is  a  modified  hatchet. 

A  spoon  is  that  class  of  excavator  Avhich  resembles  in  most  re- 
spects the  hatchet,  other  than  the  cutting  edge.  This  is  sharpened 
on  one  side  only  which  is  rounded  like  the  convex  side  of  the  bowl 
of  a  spoon  from  which  it  derives  its  name.  The  cutting  edge  is 
rounded  and  sharpened  to  a  thin  edge.  Spoons  are  always  made 
rights  and  lefts. 

The  use  of  a  spoon  is  to  remove  foreign  matter  and  softened 
dentine  from  the  tooth  cavity. 

The  angles  between  the  shank  and  the  working  part  are  desig- 
nated as  mon-angle,  bin-angles,  and  triple-angles,  according  to  the 
number  of  angles  used  being  one,  two  or  three,  respectively. 

The  contra-angle  is  the  placing  of  such  angles  in  the  shank  of 
the  instrument  as  to  bring  the  cutting  edge  near  the  central  line 
of  the  shaft  which  removes  the  tendency  to  tip  or  turn  in  the  hand 
during  use. 

Bin-angles  and  triple-angles  are  properly  made  only  when  con- 
tra-angled, provided  the  cutting  edge  is  more  than  three  millimeters 
from  the  central  line  of  the  shaft. 


INSTRUMENT    NOMENCLATURE  19 

Formula  Names.  Some  instruments  have  the  formula  stamped 
on  the  handle  in  figures.  There  are  generally  three  numbers  given. 
The  first  is  the  Avidth  of  the  hlade  in  tenths  of  a  millimeter.  The 
second  is  the  length  of  the  blade  given  in  millimeters.  The  third 
is  the  angle  of  the  l)hKle  with  its  handle  given  in  the  hundredths 
of  a  circle. 

When  a  four-numl)er  formula  is  given,  as  Avith  gingival  marginal 
trimmers,  the  second  number  in  the  name  designates  the  angle  of 
the  cutting  edge  of  the  blade  with  shaft  or  handle.  This  is  also 
given  in  the  hundredths  of  a  circle. 

A  plugg'cr  is  an  order  of  instrument  foi-  the  packing  of  material 
in  the  making  of  a  filling.  Those  for  gold  are  serrated  on  the  work- 
ing point  in  such  shape  as  to  result  in  a  surface  made  up  of  prisms. 
These  prisms  should  lie  of  exactly  the  same  size  on  all  the  i^oints 
used  in  any  individual  filling  when  packing  cohesive  gold,  as  the 
interchange  of  points  of  different-sized  serrations  causes  bridging. 
(See  manipulation  of  cohesive  gold.  Chapter  XX.) 

The  dental  engine  is  almost  indispensable  and  when  properly  used 
is  a  blessing  to  our  patients  and  a  time-saver  to  the  dentist.  How- 
ever, it  is  all  too  frequently  used,  especially  by  students  and  young 
practitioners,  to  do  things  which  can  properly  be  done  only  with 
the  hand  instruments.  The  misuse  of  the  dental  engine  has  caused 
the  public  to  regard  it  asthe  climax  of  all  pain-producing  instru- 
ments in  the  dental  office,  Avhen  in  reality,  if  that  Avhich  should  be 
done  with  the  engine  is  jiroperly  done,  only  a  few  seconds  of  pain  is 
induced  in  the  preparation  of  a  very  severe  cavity. 

The  engine  bur  is  the  woi-klng  point  of  the  engine  and  is  made 
in  many  shapes  and  sizes.  However,  those  which  are  round  and  in- 
verted cones,  Avhose  diameter  is  smaller  than  one  millimetei",  are 
most  frequently  indic;i1ed.  The  tendency  of  the  beginner  is  to  use 
too  lai'ge  burs.  Hui's  are  primarily  intended  to  cut  dentine  in  out- 
lining cavity  Avails,  and  for  undermining  enamel  to  facilitate  the 
use  of  hand  insti-iimeiils  and  1licy  should  rarclx'  conie  in  contact 
A\  ith  the  enamel. 

The  most  indispensable  use  of  the  engine  is  for  Ihc  i)olishiiig  and 
grinding  neeessary  1o  the  successful  Ici-minal  ion  of  many  A^aried 
opei-alioiis,   bolh    in   ;iii'l    o\it   of  Ihc    monlli. 

The  sharpening  of  instruments  is  of  Ihc  nlmosl  iiii])oi-1aMce  and 
is  by  no  means  accomplished  \\i1hoii1  skill.  Xo  heller  can  a  dentist 
execute  finished  work  Ihan  c;iii  ;i  1r;idcsiiiaM  whose  1ools  must  be 
keen  of  edge  if  he  is  1o  produce  1li;i1  which  is  worlliy  of  his  ci'afl. 
Again,  dull  inslrumenis  cause  an  undue  amouiil   of  pain  at  each  at- 


20  OPERATIVE    DENTISTRY 

tempt  to  cut,  whereas  when  sharp,  the  pain  is  less  and  the  effort 
in  cutting  is  materially  lessened,  resulting  in  a  saving  of  pain  to 
the  patient  and  time  and  energy  to  the  dentist.  A  hard,  smooth 
Arkansas  stone  is  the  only  suitable  abrasive  and  should  be  well 
oiled  and  wiped  with  a  cloth  after  each  use. 

Care  of  Instruments.  As  the  instruments  are  shipped  to  the  den- 
tist they  are  usually  made  and  sharpened  especially  for  the  use  in- 
tended and  care  should  be  exercised  in  sharpening  that  the  degree 
of  the  angle  of  the  beveled  edge  is  not  changed. 

Tests  for  Sharpness.  An  instrument  is  tested  for  sharpness  best 
by  placing  the  edge  with  light  pressure  against  the  finger  nail  and 
attempting  to  move  it  across  the  surface  at  right  angles  to  the 
edge.    If  it  catches  or  clings  to  the  nail  it  is  ready  for  use. 


chaptp:r  II. 

CAVITY  NOMENCLATURE. 

A  cavity  nomenclature  is  necessary  that  we  iiia\'  iiii(lej'.staii(i  one 
another  in  conversing  about  the  formation  of  cavities,  the  descrip- 
tion of  their  several  parts  and  the  nietliods  of  procedure  in  the 
preparation  of  cavities  for  fillin«rs. 

Cavities  derive  their  names  from  the  surfaces  of  the  teeth  in 
■which  they  occur.  Thus  occlusal  cavity,  buccal  cavity,  labial  cav- 
ity, etc.,  are  cavities  occu)'rinj^  in  the  surfaces  named. 


Fig.    1. — Defects  in   enamel. 

Proximal  cavities  are  those  occuj-i-inu-  in  llic  proximal  surfaces 
and  are  rlividr-d  into  two  classes,  namely,  mesial  and  distal. 

A  simple  cavity  is  one  which  involves  but  one  surface. 

A  complex  cavity  is  one  which,  either  from  decay  or  extension 
in  preparation,  involves  more  than  one  surface. 

Complex  cavities  are  named  by  combininf?  the  names  of  the  su)-- 
faces  of  tlif  tooth  involved,  as  mesio-occlusal,  disto-occlusal,  mesio- 
disto-occlusal,  etc. 

An  axial  surface  cavity  is  one  which  occurs  in  an  axial  surface. 

Cavities  are  divided  as  to  their  orij^in  into  two  j^roups. 

Firsl.  Pit  and  fissure  cavities,  which  are  those  orif^inatiiif?  in 
the  miniilc  faults  in  the  enamel.     CSee  Fiji's.  1   and  2.) 

21 


22 


OPERATIVE   DENTISTRY 


Second.  Smooth  surface  cavities,  which  are  those  occurring  on  sur- 
faces without  defects  in  the  enamel,  but  are  habitually  unclean; 
(See  Figs.  3  and  4.) 

Cavities  are  divided  according  to  similarity  in  line  of  treatment 
into  six  divisions. 

Class  One.  Those  cavities  beginning  in  structural  defects.  (Pits 
and  fissures.) 

Class  Two,  Those  cavities  in  the  proximal  surfaces  of  bicuspids 
and  molars. 

Class  Three.  Those  cavities  in  the  proximal  surfaces  of  incisors 
and  cuspids  not  involving  the  incisal  angle. 


Fig.   2. — Defects  in  enamel. 


Class  Four.  Those  cavities  in  the  proximal  surfaces  of  incisors 
and  cuspids  which  require  the  restoration  of  the  incisal  angle. 

Class  Five.  Those  cavities  in  the  gingival  third  of  the  labial, 
buccal  and  lingual  surfaces  not  originating  in  faults  in  enamel. 

Class  Six.     Abraded  surfaces. 

The  outside  walls  of  a  cavity  are  those  walls  placed  toAvard  the 
outside  surfaces  of  a  tooth  and  take  the  names  of  the  surfaces  of 
the  tooth  toward  which  they  are  placed,  as  in  an  occlusal  cavity 
the  outside  walls  are  buccal,  distal,  mesial  and  lingual,  while  the 
fifth  or  internal  wall  is  the  pulpal. 

The  pulpal  wall  is  that  inside  wall  of  a  cavity  which  covers  the 
pulp  and  is  in  a  plane  at  right  angles  to  the  long  axis  of  the  tooth. 


CAVITY    NOMENCLATURE 


23 


In  case  flie  j^ulp  is  removed  the  piilpal  wall  becomes  the  sub- 
pulpal  wall,  in  multi-rooted  teeth. 

The  axial  wall  is  the  inside  wall  of  an  axial  surface  cavity  which 
covers  the  pulp  and  is  in  a  plane  parallel  to  the  long  axis  of  the 
tooth. 


Fig.  3. — Smooth  surface  decay. 


Fig.  4. — Smooth  surfact;  decay. 

In  rase  the  pulp  is  removal  in  ;iii  axial  sui-face  cavity  the  axi.al 
wall  becomes  an  outside  wall  and  takes  llic  name  of  llie  surface  of 
tlic  tooth  lowarfl  Avhich   il    is  placed. 

The  gingival  wall   is  the   inside   wall    of  an   axial   surface  cavity 


OPERATIVE    DENTISTRY 


placed  toward,  and  running  in  the  same  plane  as,  the  gingivae. 

Both  ging-ival  and  sub-pulpal  walls  may  be  present  in  cases  of 
pulp  removal  in  mesio-occlusal,  disto-occlusal,   and  mesio-disto-oc- 


Fig.  5. — Class  One  cavities  filled. 


Fig.  6. — Class  Two  cavity  filled. 

clusal  cavities  when  each  is  on  a  different  level  and  the  individuality 
of  each  wall  is  retained. 

The  inside  walls  of  a  cavity  are  those  placed  toward  the  pulp  or 
root  of  a  tooth. 


CAVITY    NOMENCLATURE 


25 


The  base  of  a  cavity,  or  seat  of  a  filling,  is  that  portion  of  a  cav- 
ity situated  at  right  angles  to  the  lines  of  force  to  Avhich  it  is  most 
likely  to  be  subjected.  Generally  speaking,  this  is  the  gingival  or 
pulpal  M-all,  or  both,  where  these  Avails  are  present,  as  in  a  step 
cavitv. 


Fig.    7. — Class    Three    cavity    filled. 


Fig.    8. — Class    Four    cavity    filled. 


Fig.    9. — Class   Five   cavity   filled. 


A  line  angle  is  formed  where  two  walls  of  a  cavity  meet  along 
a  line  and  is  named  by  joining  the  names  of  the  Avails  so  meeting. 

There  is  hut  one  exception  to  this  rule.  That  is  whoi-e  the  labial 
and  lingual  walls  of  a  proximal  cavity  in  the  incisoi-s  and  cuspids 
meet  along  a  line.     By  applying  the  rule  this  Avould  be  called  the 


26 


OPERATI\"E    DENTISTRY 


labio-ling'ual  angle,  but  for  convenience  this  is  named  the  ''incisal- 
line  angle." 

A  point  angle  is  formed  where  three  walls  of  a  cavity  meet  at 


Fig.  10. — Bisected  molar  in  which  a  mesial  Class  Two  cavity  has  been  cut  and  line  angles 
indicated.  The  line  angles  are:  a,  Gingivo-buccal;  b,  Gingivo-lingual;  c,  Gingivo-axial;  d, 
Axio-buccal;  e,  Axio-lingual;  /,  Axio-pulpal;  g,  Pulpo-buccal;  h,  Pulpo-lingual;  i,  Pulpo-distal; 
j,  Disto-buccal;   k,   Disto-lingual. 


.  Fig-  11-— Bisected  molar  m  which  a  mesial  Class  Two  cavity  has  been  cut  and  point  angles 
indicated.  The  point  angles  are:  a,  Gingivo-axio-buccal ;  b,  Gingivo-axio-Iingual;  d,  Pulpo-disto- 
lingual;   e,  Pulpo-disto-buccal. 


a  point  and  is  named  by  joining  the  names  of  the  walls  so  meeting. 
Tliere  is  hut  one  exception  to  tJiis  rule.    The  point  of  junction  of 


CAVITY   NOMENCLATURE 


27 


the  axial,  labial  and  lingual  walls  in  proximal  cavities  in  the  six 
anterior  teeth  is,  for  convenience,  named  the  "ineisal  angle." 

A  simple  cavity  has  two  sets  of  line  angles.  First,  the  internal 
line  angles  surrounding  the  internal  wall,  which  is  the  axial  wall 
in  axial  surface  cavities,  and  the  pulpal  wall  in  occlusal  cavities. 

The  second  set  of  external  line  angles  is  formed  by  the  junc- 
tion of  the  outside  walls  with  each  other. 

The  enamel  margin  is  that  point  on  the  surface  of  the  tooth 
where  the  cavitv  begins  in  enamel. 


Fig.   12. — A,  External  enamel  surface;  B,  Cavo-surfacc  angle;   C,  Marginal  bevel;  D,  Bevel 
angle;  E,  Enamel  wall;  F,   Dento-enamel  junction;   G,  Dentinal  wall;     H,  Base  line  angles. 


The  external  enamel  line  is  tlie  entire  outline  of  the  cavity  at 
its  erianic]  iiiarj^in. 

The  cavo-surface  angle  is  the  angle  foi-med  by  the  junction  of 
tlif  \\;ill  of  the  caNily  with  the  external  surface  of  tlie  tooth. 

The  base  of  the  cavo-surface  angle  is  the  external  enamel  surface. 

The  marginal  bevel  of  a  cavity  is  the  dcdeclion  of  a  cavity  wall 
fr'om   its  eslahlislictl    plane,   near  the   exlenial    cnaniel    line. 

It  is  necessary  that  beveling  be  resorted  to,  in  order  to  manage 


28  OPERATIVE    DENTISTRY 

the  enamel  margins,  direct  the  external  enamel  line  and  control 
the  degree  of  the  cavo-surface  angle,  Avithont  disturbing  the  gen- 
eral retentive  form  of  the  cavity. 

The  bevel  angle  is  the  angle  formed  by  the  junction  of  the  mar- 
ginal bevel  with  the  remaining  portion  of  the  wall  of  which  it  is  a. 
part. 

The  base  of  the  bevel  angle  is  the  remaining  portion  of  the  cavity 

wall. 

The  bevel  angle  is  covered  when  the  filling  is  in  position.  Its 
distance  from  the  enamel  margin  depends  upon  the  filling  material 
used,  and  the  location  in  the  cavity  outline.  To  illustrate :  With 
porcelain  inlays  and  amalgam  the  bevel  angle  must  be  deeply  bur- 
ied, resulting  in  a  thicker  edge  of  filling  material.  With  cast  gold 
inlays  and  platinum  combination  fillings  the  bevel  angle  should  be 
near  the  surface,  resulting  in  a  short  marginal  bevel.  The  distance 
of  the  bevel  angle  from  the  cavo-surface  angle  must  not  affect  the 
degree  of  the  latter  angle  but  determines  only  the  length  of  the 
bevel  and  the  thickness  of  the  filling  at  its  margin. 

The  planes  of  a  tooth  are  three  in  number ;  horizontal  plane,  mesio- 
distal  plane  and  bucco-lingual  plane. 

The  horizontal  plane  is  at  right  angles  to  the  long  axis  of  the 
tooth. 

The  mesio-distal  plane  passes  through  the  tooth  from  mesial  to 
distal  parallel  with  the  long  axis. 

The  bueco-lingnal  plane  passes  through  the  tooth  from  buccal  to 
lingual  parallel  with  the  long  axis  of  the  tooth.  In  the  six  anterior 
teeth  this  plane  would  be  labio-lingual. 


CHAPTER  III. 
CAVITY  PREPARATION.     ( GENERAL  CONSIDERATIONS. ) 

Definition  of  Cavity  Preparation.  Cavity  preparation  is  that  term 
applied  to  those  mechanical  procedures  upon  a  tooth,  looking  to 
the  making  of  a  filling,  as  well  as  those  changes  and  extensions 
necessary  to  resist  stress  and  prevent  a  recurrence  of  decay. 

Aff'ected  Dentine  is  dentine  which  has  been  acted  upon  by  the 
lactic  acid  in  adxaiice  of  the  micro-organisms  of  caries. 

Infected  Dentine  is  dentine  which  has  been  penetrated  by  micro- 
organisms. 

Objects  in  Filling-  Teeth.  There  are  four  general  objects  in  vicAv 
in  the  filling  of  teeth : 

First. — To  arrest  the  loss  of  tooth  substance. 

Second. — To  prevent  recurrence  of  caries. 

Tliird. — To  restore  full  tooth  contour. 

Fourfli. — To  improve  the  primary  conditions  as  to  the  perform- 
ance of  function  and  esthetic  effects. 

A  Completed  Cavity  should  be  a  combination  of  flat  walls  com- 
ing together  at  definite  angles,  surrounded  by  an  external  line  made 
up  of  the  largest  curves  permissible. 

The  Line  Angles  within  a  cavity,  which  are  a  necessary  part  of 
resistance  and  retention  forms,  should  never  be  permitted  to  end 
in  the  external  enamel  line. 

Order  of  Procedure.  To  simplify  the  preparation  of  all  cavities 
and  to  insure  tiie  (jbservance  of  certain  fundamental  principles  it 
is  Avell  to  follow  a  definite  order  of  procedure.  This  will  greatly 
facilitate  the  operations  of  the  student  and  lead  to  the  establish- 
ment of  habits  by  the  practitioner  which  Avill  stand  for  thorough 
methods  of  execution. 

The  following  would  seem  to  be  the  iiatnial  ordci- : 

First. — Gain  access. 

Second. — Outline  form. 

Third. — Resistance  form. 

Fo}irlk. — Retention  form. 

Fifth. — r'onvcnicnce  form. 

Sixth. — Removal  of  remaining  decay. 

Seventh. — Finishing  of  enamel  walls. 

Eighth. — Toilet  of  the  cavity. 

29 


30  OPERATIVIS   DENTISTRY 

Modification  of  Form  is  necessary  in  cavity  preparation  to  meet 
the  various  properties  of  the  different  filling  materials  used.  This 
is  particularly  true  when  considering  the  difference  in  edge  strength 
and  flow  of  metals  and  alloys. 

The  character  of  the  oral  fluids,  the  evident  care  bestowed  upon 
the  teeth,  condition  of  patient's  health,  age  of  patient  and  the  life 
expectancy  of  the  patient  and  of  the  individual  teeth,  will  fre- 
quently require  a  modification  of  cavity  formation  to  best  resist 
the  recurrence  of  decay  and  the  dislodgement  of  the  filling  through 
stress. 


CHAPTER  IV. 
GAINING  ACCESS. 

Definition,  (iaiiiing  access  is  the  term  applied  to  those  proced- 
ures necessary  to  make  sufficient  room  for  the  i^roper  introduction 
of  the  filling. 

Sufficient  Access  is  Important,  that  ^ve  may  have  the  advantage 
of  space  to  projDcrly  handle  the  instruments  and  appliances  used 
in  the  procedures  of  making  a  filling,  that  we  may  be  al)le  to  intro- 
duce the  filling  into  the  cavity,  that  there  may  be  complete  contour 
restoration  of  tooth  form  and  that  the  desired  contact  relation  may 
be  established  to  the  adjacent  tooth. 

Access  to  the  Tooth  is  the  first  consideration  and  will  involve 
the  opening  of  the  mouth  to  a  sufficient  degree  to  permit  of  the 
free  use  of  the  usual  appliances.  The  i:)roximal  spaces  used  for  the 
adjustment  of  the  dam  should  be  examined  to  make  sure  that  the 
rubber  and  ligatures  Avill  pass  to  the  gingival  line  without  injury. 
A  sufficient  number  of  teeth  should  be  isolated,  say  four  or  five, 
to  give  a  clear  and  unobstructive  view  of  the  cavity  and  surround- 
ing teeth. 

The  operator  must  be  able  to  bring  the  cavity  into  full  view. 
Cases  where  there  has  been  considerable  decay  sub-gingivally,  and 
tumefaction  of  the  gum  septa  has  taken  place,  proper  access  Avill 
involve  the  packing  of  the  cavity  with  a  tampon  of  cotton  Avhich 
has  been  dipped  in  chlora-percha,  oi-  a  packing  of  gutta-percha, 
for  a  period  of  twenty-four  or  forty-eight  hours,  to  crowd  the  en- 
croaching gum  tissue  from  the  cavity.  A  neglect  of  this  considera- 
tion of  access  Avill  often  make  proper  management  of  the  gingival 
wall  and  margin  most  difficult  oi-  imp()ssil)]e. 

Surgical  Access  may  be  practic(Ml  on  the  cavity  mai-giiis,  A\heii 
all  tooth  structure  thus  removed  w  ill  subsequently  be  replaced  wilh 
filling  material.  It  may  be  practiced  on  the  gum  septa  when  there 
has  been  excessive  tumefaction  in  the  pi-oximal  space. 

Formerly  this  method  Avas  practiced  wilh  Class  I^Mve  cavities 
where  the  decay  Avas  to  a  marked  cxlciit  subgingival,  and  it  A\as 
desired  to  make  a  cohesive  gold  filling.  However,  nnich  of  this 
f|uestional>le  practice  may  now  be  avoided  by  the  use  of  the  gold 
inlay,  made  from  the  wax  model,  as  llic  pi-cscncc  of  tlic  ovci'lying 
gum   is  no  fonsidf'i-al)l('  liindranec. 

Access  as  Related  to  Restoration  of  Proximal  Space.     As  tooth 

31 


32  OPERATIVE    DENTISTRY 

substance  is  lost  through  decay  in  proximal  cavities,  there  is  in 
most  cases  a  movement  of  the  teeth  to  the  proximal,  encroaching 
on  the  normal  space,  robbing  the  gum  of  sufficient  room  for  full 
festoon.  It  is  wholly  impossible  in  such  cases  for  the  operator  in 
making  a  filling  to  restore  tooth  contour,  or  leave  a  normal  amount 
of  room  for  the  rehabitation  of  the  gum  septa,  without  resorting 
to  separation.  The  surfaces  of  a  tooth  which  are  covered  with 
healthy  gum  tissue  are  practically  immune  from  both  prim.ary  and 
secondary  caries,  and  it  is  greatly  to  the  advantage  of  a  filling,  the 
outline  of  which  in  the  proximal  gingival  third,  to  be  so  protected. 
Good  access  should  be  gained  by  preliminary  separation,  so  that 
when  the  completed  filling  with  its  full  tooth-form  restoration  is 
in  place,  there  is  restored  the  normal  proximal  space  for  the  habita- 
tion of  the  gum  septa.  A  failure  to  regard  this  fact  will  result  in 
a  strangulated,  diseased  and  dwarfed  septa,  inviting  an  accumula- 
tion of  the  enemy  of  tooth  structure  and  an  early  loss  of  the  filling 
through  secondary  caries. 

Restoration  of  Tooth  Form  is  essential  that  the  full  function  of 
the  masticating  organs  may  be  established  and  maintained.  It  is 
also  desirable  for  esthetic  reasons,  as  the  more  nearly  a  dentist 
approaches  complete  tooth  contour  restoration,  with  all  its  details, 
the  more  pleasing  is  the  appearance  and  the  more  artistic  the 
result. 

Proper  Contact  Point  is  often  impossible  unless  sufficient  ac- 
cess has  been  secured  through  separation.  This  contact  should 
be  a  point  of  contact,  the  embrasures  widening  therefrom  in  every 
direction.  It  should  be  in  no  sense  a  line  of  contact  or  a  surface, 
no  matter  how  small.  It  is  advisable  many  times,  in  this  respect, 
to  improve  on  nature  by  slightly  varying  the  surface  of  the  filling 
from  the  original  shape  of  the  tooth,  as  often  the  predisposing  cause 
of  the  primary  decay  has  been  defective  contact. 

The  Saving-  of  Tooth  Substance  is  materially  effected  by  access 
through  preliminary  separation,  particularly  in  the  placing  of  in- 
lays, as  the  more  thoroughly  this  first  step  in  procedure  has  been 
accomplished  the  less  cutting  will  be  required  for  convenience  form, 
a  point  of  no  small  importance. 

Methods  of  Separation.  There  are  two  classifications  of  separa- 
tion to  gain  access,  preliminary,  which  is  also  slow  separation,  and 
immediate,  which  is  rapid,  both  of  which  are  a  part  of  gaining  ac- 
cess. 

The  preliminary  is  a  part  of  the  first  consideration,   while   im- 


GAINING   ACCESS  33 

mediate  separation  is  brought  to  our  attention  during  the  introduc- 
tion of  the  filling. 

Preliminary  Separation  is  best  accomplished  in  proximal  cavities 
in  bicuspids  and  molars  (Class  Two)  by  packing  into  the  partially 
excavated  cavity  an  excess  of  gutta-percha  base  plate.  A  few  days, 
or  in  some  instances  a  few  weeks,  will  suf^ce  to  accomplish  the 
desired  result,  particularly  if  the  patient  uses  that  location  in  the 
mouth  for  daily  mastication  of  solid  food. 

In  the  proximal  space  in  the  six  anteriors  pi-eliminary  separa- 
tion is  best  accomplished  by  the  use  of  cotton  tampons  tightly 
packed  ill  the  ca\it}-  and  ligatured  securely  to  position. 

Immediate  Separation  is  best  accomplished  with  the  mechanical 
separator,  and  should  be  used  to  gain  additional  access,  not  already 
secured  by  preliminary  separation,  or  may  be  used  primarily  when 
only  a  small  amount  of  additional  space  is  desired.  This  instru- 
ment should  be  adjusted  as  soon  as  convenient  after  securing  out- 
line form,  and  removed  only  Avhen  the  filling  is  finished. 

Avoid  Gum  Injuries  in  the  use  of  elastic  rubber.  In  the  use  of 
the  methods  given  care  should  be  used  not  to  ci-owd  the  gum  tissue 
as  permanent  injury  may  result. 

There  are  other  materials  used  in  slow  separation,  as  linen  tape, 
wooden  wedges,  etc.,  each  with  its  merit  and  indicated  use. 

Soreness  Resulting  from  Tooth  Separation  should  be  treated  as 
any  case  of  acute  pericementitis,  by  giving  the  tooth  physiological 
rest,  and  the  use  of  stimulating  applications  on  the  gum  over  the 
tooth's  root. 


CHAPTER  V. 
OUTLINE  FORM. 

Definition.  Outline  form  is  that  part  of  cavity  preparation  which 
determines  the  area  of  the  tooth  surface  to  be  included  within  the 
external  enamel  line. 

Rule  1.  Extend  to  Sound  Enamel.  All  cavity  margins  should 
be  extended  until  all  indications  of  surface  decay  have  been  in- 
cluded. 

Rule  2.  Obtain  Full  Length  Rods.  If  necessary,  further  extend 
the  outline  until  full-length  enamel  rods,  supported  by  sound  den- 
tine, have  been  reached. 

Rule  3.  Self -Cleansing  Margins.  Extend  the  cavity  outline  un- 
til the  surface  of  the  filling  can  be  so  formed  that  the  enamel  mar- 
gin not  protected  by  the  gum  will  be  mechanically  cleansed  by  the 
excursions  of  food  in  mastication. 

Rule  4.  In  Relation  to  Developmental  Grooves.  A  cavity  out- 
line should  not  follow  a  developmental  groove,  or  parallel  it  so 
closely  as  to  leave  a  small  strip  of  intervening  enamel.  The  outline 
should  cross  the  grooves  as  squarely  as  possible. 

Rule  5.  Fissures  and  Sulcate  Grooves.  All  fissures,  sulcate 
grooves  and  angular  developmental  grooves  encountered  should  be 
included  within  the  cavity  outline.  This  comes  in  for  the  greatest 
consideration  when  part  of  the  outline  is  laid  on  an  occlusal  sur- 
face. 

Rule  6.  Enamel  Eminences.  The  outline  should  avoid  extreme 
eminences  of  enamel  and  centers  of  primary  development.  Such 
locations  are  subject  to  the  extremes  of  stress  during  mastication. 
When  the  eminence  in  question  is  the  seat  of  primary  calcification 
it  will  be  found  to  be  less  perfect  in  formation  than  the  portion 
midway  from  that  point  to  the  grooves. 

Rule  7.  Avoid  Angles  in  Outline.  The  outline  should  be  made 
up  of  the  greatest  curves  possible,  avoiding  all  angles.  Nearly  flat 
axial  surfaces  should  show  nearly  straight  lines  or  the  segments 
of  very  large  circles,  while  on  occlusal  surfaces,  which  are  made  up 
of  a  succession  of  depressions  and  eminences,  the  outline  should 
be  a  combination  of  smaller  curves. 

Rule  8.  Outline  in  the  Embrasures.  The  outlines  in  the  labial, 
buccal  and  lingual  embrasures  should  be  parallel  to  each  other  and 

34 


OUTLINE    FORM 


35 


at  right  angles  to  the  seat  of  the  cavity,  and  pass  under  the  free 
margin  of  the  gum  at  a  point  in  full  view  of  the  operator. 

Rule  9.  Enamel  Margins.  The  enamel  margins  should  be  planed 
smooth  to  a  full  cleavage  of  the  enamel  rods  and  then  slightly 
beveled  that  the  rods  at  the  cavo-surface  angle  may  be  full-length 


Fig.    13. — Teclinic   group   illustrating  outline   form. 


Fig.   14. —  Another  view  of  cavities  illustrated  in  Fig.   13. 

I'od.s,  supported  l)y  shortened  enamel  i-ods  which  are  ])r()tected  by 
the  o\'crlyiim-  filling-  iii;itei-i;il. 

Rule  10.  Extension  for  Prevention.  Wlicn  ])(»ssihle,  carry  the 
cavity  out  line  upon  snmolli,  uM<'lcan  .surfaces,  from  an  area  of  great 
liability  to  caries  to  an  area  of  lesser  liability  1o  caries. 

This  has  reference  to  caries  of  enamel  onlv  and  will  ccmie  into 


36 


OPERATIVE    DENTISTRY 


consideration  in  cavity  outline  when  the  rules  previously  given  i 
have  not  carried  the  outline  to  comparatively  safe  and  immune  ] 
localities.  \ 


Fig.    IS. — Fillings  in  place  in   cavities  shown   in   Figs.    13   and    14. 


Fig.   16. — Another  view  of  fillings  shown  in  Fig.   15. 

Extension  for  prevention  does  not  mean  tJie  consideration  of  re- 
sistance to  stress.  It  bears  no  reference  to  decay  of  the  dentine.  It 
has  no  relation  to  the  management  of  frail  walls. 


OUTLINE    FORM  37 

Ifs  }n(t.ri)uu)n  tipiAicdiion  is  found  in  the  management  of  small 
cavities  where  the  ravages  of  decay  have  not  yet  carried  the  out- 
line of  the  cavity  to  areas  not  subject  to  pi'imary  enamel  dissolu- 
tion. 

Tlie  abuses  of  extension  ferr  prevention  result  in  much  unneces- 
sary loss  of  tooth  substance,  while  its  sane  and  legitimate  use  is  one 
of  the  most  important  factors  in  tooth  salvage. 

Dangers  of  Increased  Cavity  Outline.  The  danger  of  secondary 
caries  increases  in  each  mouth  proportionately  as  the  aggregate 
length  of  cavity  outline  is  increased. 

To  IJlusfrafi.  If  the  total  length  of  cavity  outline  of  all  fillings 
in  a  mouth  is  doubled  by  the  increase  in  numl^er  of  fillings  the 
lia])ility  to  secondary  caries  is  doubled,  all  else  being  equal.  For 
that  reason  each  individual  cavity  should  have  its  outline  as  short 
as  permissible. 

The  laying  of  cavity  outline  in  locations  not  suscepti]:)le  to  pri- 
mary caries  "will  materially  decrease  the  liability  to  recurrent  de- 
cay, even  though  the  aggregate  cavity  outline  in  the  mouth  is 
thereby  greatly  lengtiiened.  An  aggregate  cavity  outline  of  two 
feet  is  preferable  to  a  total  of  one  foot,  provided  the  additional 
1-^ngth  has  been  caused  to  extend  to  locations  not  lia])le  to  caries. 


CHAPTER  VI. 
EESISTANCE  FORM. 

Definition. — Extension  for  resistance  is  a  term  applied  to  that 
procedure  whicli  has  for  its  sole  object  the  carrying  of  the  cavity 
outline  from  localities  subjected  to  great  stress,  to  localities  not 
frequently  subjected  to  the  crushing  strain.  This  is  often  mistaken 
for  extension  for  prevention,  whereas  it  has  reference  only  to  re- 
sistance to  stress. 

A  proper  application  of  this  procedure  will  involve  a  careful 
study  of  occlusion  and  articulation  in  each  individual  case. 

Resistance  form  involves  a  consideration  of  the  management  of 
weakened  enamel  walls  and  a  stud}^  of  the  flow  and  edge  strength 
of  the  filling  material  used  with  a  view  of  so  shaping  the  cavity 
as  to  minimize  the  effects  of  the  crushing  strain. 

Its  importance  is  in  direct  proportion  to  the  exposure  of  the  fill- 
ing in  occlusion  and  articulation,  and  the  strength  of  the  closure 
of  the  jaAvs. 

The  force  to  provide  for  is  from  one  to  two  hundred  pounds  and 
in  some  cases  even  more,  particularly  in  mid- jaw  locations. 

Weakened  enamel  walls  are  those  which  through  decay,  or  un- 
necessary cutting,  have  been  robbed  of  much  of  their  supporting 
dentine.  All  such  unsupported  enamel  should  be  cut  away  with  a 
chisel,  particularly  if  by  any  chance  the  wall  of  enamel  under  con- 
sideration Avill  receive  much  stress  in  the  process  of  mastication, 
or  the  introduction  of  the  filling. 

Stress  from  within  should  be  avoided  by  not  allowing  such  weak- 
ened walls  to  remain  and  form  any  part  of  the  retention  of  the 
filling. 

Weakened  walls  are  sometimes  allowed  to  remain,  or  a  portion 
of  them,  when  they  can  be  so  protected  by  a  layer  of  rigid  filling 
material  as  to  prevent  all  stress,  but  this  is  permissible  only  when 
their  presence  will  screen  unsightly  metal  fillings  and  when  the 
kind  of  filling  used  can  be  introduced  Avithout  injury  to  the  walls. 

Before  applying  the  rubber  dam  each  case  should  be  inspected 
for  the  surface  contact  in  occlusion  and  articulation  and  then  the 
margin  so  laid  as  to  occupy  the  least  exposed  position.  Many  times 
all  stress  cannot  be  avoided,  but  the  amount  of  stress  a  margin  is 
liable  to  receive  should  have  due  consideration  and  good  judgment 
exercised  in  the  placing  of  the  margin. 

38 


RESISTANCE  FORM  39 

Resistance  Form  as  Applied  to  Filling  Material.     We  are  forced 

to  eoii.sider  the  properties  of  the  filling  material  to  be  used  in  each 
individual  cavity.  In  preparing  the  cavity  we  consider  the  resist- 
ing power  of  the  enamel  margin  we  are  a])le  to  obtain.  We  also 
take  into  account  the  resistance  of  the  filling  material  used,  to  the 
crushing  strain,  as  this  property  varies  greatly.  Amalgam,  even 
under  the  most  favorable  manipulation,  is  subject  to  flow  and  more 
or  less  spheroiding,  which  often  results  in  a  slight  exposure  of 
the  cavo-surface  angle.  Again,  amalgam  is  not  ductal,  hence  these 
edges  of  this  filling  are  easily  fractured  at  the  margins  under 
stress.  This  liability  to  fracture  at  the  margin  is  also  true  of  our 
cement  and  silicate  fillings  and  great  care  should  be  exercised  in 
placing  the  margins  of  these  fillings.  Cohesive  gold,  especially 
Avhen  alloyed  with  platinum,  is  our  best  filling  material  to  resist 
the  crushing  strain  at  the  margins,  and  when  the  edges  are  not  too 
thin,  the  repeated  blows  from  the  opposing  teeth  only  tend  to  drive 
this  material  in  closer  adaptation  to  the  margins.  When  using  the 
gold  inlay,  it  is  quite  necessary  to  exercise  great  care  at  the  mar- 
gins to  resist  the  crushing  strain,  not  of  the  gold,  but  of  the  en- 
amel margin  and  the  intervening  cement,  for  unless  the  gold  in- 
lay fits  better  than  the  average  gold  inlay,  there  is  a  line  of  ce- 
ment which  is  subsequently  dissolved.  This  leaves  the  last  rods  at 
the  cavo-surface  angle  unprotected,  and  very  liable  to  injury. 

It  therefore  follows  that  the  amount  of  marginal  extension  for 
resistance  form  is  less  for  cohesive  gold  and  gold  inlays  than  other 
fillings.  The  greater  the  edge  strength  of  the  filling  matei-ial,  the 
more  protection  it  gives  the  cavity  margins.  Yet  resistance  form 
should  receive  careful  consideration  with  fillings  of  maximum  edge 
strength. 


CHAPTER  VII. 
RETENTION  FORM. 

Definition.  Retention  form  is  that  part  of  the  procedure  in  cav- 
ity preparation  which  deals  with  the  provisions  for  preventing  the 
filing  from  being  displaced  by  the  tipping  strain.  Force  which 
results  in  tipping  the  filling  bodily  from  the  cavity,  is  one  of  the 
greatest  enemies  to  permanency  in  tooth  filling,  second  only  to  re- 
current caries. 

Partially  Provided  For  in  R-esistance  Form.  Retention  form  is 
partially  provided  for  in  the  previous  step  of  resistance  form,  but 
it  is  further  necessary  that  provision  be  made  to  resist  the  force  of 
mastication  in  order  to  prevent  the  filling  as  a  whole  from  being 
moved  from  its  seat. 

Maximum  Retention  Form  is  required  in  cavities  in  the  proximal 
surfaces  as  the  missing  proximal  wall  renders  these  fillings  particu- 
larly exposed  to  injury  by  the  tipping  force,  during  the  movements 
of  the  mandible. 

Flat  seats  for  fillings  are  imperative  in  retention  form.  Seats 
should  be  cut  in  a  plane  at  right  angles  to  the  stress  of  mastica- 
tion, which  is  usually  at  right  angles  to  the  long  axis  of  the  tooth. 

The  Step  as  a  Part  of  Retention  Form.  The  addition  of  the  step 
in  cavities  of  Class  Two  and  Class  Four  is  for  the  purpose  of  giving 
added  retention  form.  By  this  procedure  in  proximal  cavities  in 
bicuspids  and  molars,  the  stress  upon  buccal  and  lingual  walls  of 
the  cavity  proper  is  transferred  to  those  portions  of  the  same  walls 
which  are  a  part  of  the  step,  a  location  much  better  situated  to 
withstand  the  tipping  strain.  In  cavities  of  Class  Four,  the  addi- 
tion of  the  step  on  the  incisal  or  lingual,  or  both,  will  give  added 
retention  form,  avoiding  heavy  cutting  at  the  angle,  which  weakens 
the  remaining  tooth  substance  at  the  angle,  to  say  nothing  of  the 
dangers  of  crossing  the  retractive  tract  of  the  pulp  in  this  location. 

Maximum  Retention  Form  is  not  required  when  making  simple 
cavities,  as  they  are  protected  from  the  dangers  of  lateral  strain 
by  the  presence  of  surrounding  external  walls.  This  will  be  found 
to  be  the  case  in  cavities  of  Classes  One,  Three  and  Five  when  oc- 
clusion is  normal.  While  in  cavities  of  Classes  Two,  Four  and  Six, 
much  additional  cutting  is  sometimes  necessary  to  give  ample  re- 
tention form. 

Acute  Angles  Required.     Much  of  the  retention  form  required 

40 


RETEXTIOX    FORM  41 

is  gained  by  laj-ing  the  external  surrounding  Avails  at  definite  angles 
to  the  seat  of  the  filliiiu'. 

Little  Retention  in  Enamel.  It  should  be  remembered  in  this 
step  of  cavity  preparation  that  there  is  very  little  resistance  to 
force  in  a  filling  wherein  retention  form  is  provided  for  in  enamel 
walls.  The  enamel  should  be  removed  to  a  depth  sufficient  to  get 
anchorage  in  angles  laid  in  dentine.  A  good  idea  of  the  amount 
of  retention  form  possessed  ])y  any  completed  cavity  may  be  gained 
if  one  will  for  the  time  being  imagine  that  all  enamel  has  been  re- 
moved from  the  tooth.  The  remaining  cavity  Avill  still  have  nearly 
the  original  amount  of  retention  form.  We  rely  upon  the  presence 
of  enamel  in  liable  areas  for  resistance  to  recurrent  caries  and  upon 
.sound  dentine  for  retention  form. 


CHAPTER  VIII. 
CONVENIENCE  FORM. 

Definition.  Convenience  form  is  that  part  of  cavity  preparation 
wherein  is  made  those  additional  changes  necessary  for  the  proper 
placing  of  a  filling. 

Sparingly  Used.  As  these  additional  cavity  changes  and  their 
accompanying  loss  of  tooth  substance  are  made  entirely  for  the 
convenience  of  the  operator  they  should  be  resorted  to  only  in  cases 
of  necessity. 

Maximum  Convenience  Form.  The  cutting  necessary  for  con- 
venience form  reaches  the  maximum ;  first,  with  inlay  fillings,  as 
the  previously  prepared  filling  is  moved  to  position  en  masse ;  sec- 
ond, in  the  making  of  a  cohesive  gold  filling,  as  it  is  of  value  to 
apply  force  as  near  as  possible  at  a  right  angle  to  the  anchorage 
of  the  first  portion  of  gold,  and  at  an  angle  of  45  degrees  to  the 
wall  against  which  the  gold  is  being  condensed ;  third,  in  cavities 
in  the  posterior  teeth,  and  in  distal  cavities  as  compared  with  mesial ; 
fourth,  more  is  required  for  proximal  fillings  not  previously  sepa- 
rated. 

Minimum  Convenience  Form  is  required;  first,  in  using  plastic 
fillings ;  second,  in  anterior  oral  locations ;  third,  where  the  teeth 
have  had  ample  separation  before  the  making  of  a  proximal  filling. 

The  Abuse  of  Convenience  Form  is  of  harm  to  the  teeth  and  has 
reached  its  height  in  a  desire  to  inlay  every  case  possible.  When 
excessive  cutting  for  convenience  form  is  necessary  to  the  making 
of  an  inlay,  it  would  often  be  better  to  avoid  the  unnecessary  loss 
of  tooth  substance  b^v^  changing  the  character  of  the  filling. 

Suitable  Instruments  for  various  locations  in  the  mouth,  par- 
ticularly with  the  posterior  distal  cavities,  will  do  much  to  minimize 
convenience  form. 

Previous  Separation  is  the  most  potent  factor  of  all  in  lessening 
the  amount  of  cutting  for  convenience  form,  the  same  having  been 
considered  fully  in  access  form,  and  should  be  resorted  to  in  cav- 
ities of  Classes  Two  and  Three  if  for  no  other  reason. 

Starting  Points  for  the  making  of  a  cohesive  gold  filling  are  a 
part  of  convenience  form  and  are  made  by  making  one  of  the 
point  angles  more  acute  than  is  required  for  general  retention. 
This  is  made  in  the  point  angle  farthest  from  the  hand  when  the 

42 


COXVENIEXCE    FORM  43 

same  is  in  position  with  the  plugger  point  resting  in  the  cavity. 
This  will  be  fonnd  to  be  the  point  angle  farthest  from  vision  and 
.most  difficult  to  fill,  and  from  the  latter  fact  should  be  the  first 
filled. 


CHAPTER  IX. 

REMOVAL  OF  REMAINING  CARIOUS  DENTINE.— FINISHING 
ENAMEL  WALLS.— TOILET  OF  THE  CAVITY. 

Eemoval  of  Remaining'  Carious  Dentine. 

Definition.  This  order  is  the  secondary  consideration  of  af- 
fected dentine.  In  the  smaller  cavities  the  previous  steps  in  cav- 
ity preparation  will  have  removed  all  affected  dentine  and  this  step 
has  little  consequence.  However,  it  is  well  to  have  this  step  come 
to  the  mind  even  in  these  cases  so  that  the  minute  corners  and  ob- 
scure localities  are  not  allowed  to  pass  imperfectly  prepared. 

In  Large  Decays  the  pulp  is  often  in  question.  The  dentine  has 
been  softened  to  a  near  approach  to  the  pulp.  If  all  of  this  be  re- 
moved early  in  the  procedure,  the  pulp  Avill  be  exposed  to  the  dam- 
aging effects  of  air  drafts  from  the  chip  blower,  or  possibly  low 
temperatures  in  the  operating  room.  Pulps  thus  exposed  not  in- 
frequently take  on  the  initial  stages  of  destructive  diseases  from 
which  they  never  recover,  resulting  in  much  pain  to  the  patient 
and  chagrin  to  the  operator.  The  foregoing  is  particularly  true 
when  one  is  making  a  filling  for  each  of  two  large  proximal  cavities. 

Two  Large  Proximal  Cavities.  It  is  often  desirable  to  prepare 
both  cavities  at  the  same  sitting,  particularly  when  filling  with 
amalgam. 

With  the  cavity  first  prepared,  there  might  be  a  long  exposure 
of  the  pulp  to  a  lower  than  body  temperature,  if  the  overlying  de- 
cayed dentine  is  removed  at  the  time  the  major  jDortion  is  ex- 
cavated. 

Technic.  The  remaining  decay  in  this  step  of  procedure  should 
be  removed  with  broad  spoon  excavators,  when  working  on  axial 
or  pulpal  walls.  In  small  cavities  where  there  is  no  danger  of  pulp 
exposure  the  instruments  should  be  small  hatchets,  with  which  the 
dento-enamel  junction  should  be  examined  around  the  entire  cav- 
ity. In  case  a  softened  area  is  found  and  removed  the  overlying 
enamel  should  be  chiseled  aAvay,  thus  restoring  the  correct  out- 
line. 

Where  Exposed  Pulp  is  expected  or  pulp  treatment  is  intended, 
the  decay  is  removed  just  following  outline  form. 

44 


TOILET    OF    THE    CAVITY  45 

Finishing'  Enamel  Walls. 

Definition.  The  last  cutting  done  in  the  preparation  of  a  cavity 
is  the  finishing  of  enamel  walls.  This  should  ahvays  be  done  with 
the  rubber  dam  in  place  or  at  least  sufficient  means  taken  to  pre- 
A'ent  the  margins  from  again  becoming  moist. 

No  Moisture  should  be  Permitted  to  come  in  contact  with  any 
portion  of  the  cavity  surface,  after  final  instrumentation,  and  if 
by  accident  any  portion  should  become  wet  that  portion  should  be 
thoroughly  dried  and  freshened  ])y  cutting  away  the  surface,  and 
the  filling  immediately  placed. 

The  Cavo-surface  Angle  of  the  cavity  in  every  part  of  the  cavity 
outline  should  receive  special  attention  at  this  step  in  cavity  prep- 
aration. 

The  Plane  of  the  Enamel  \\all  should  be  so  laid  Avith  reference 
to  the  cleavage  of  the  enamel  that  these  will  be  cut  more  from  the 
outer  than  the  inner  ends  of  the  rods,  resulting  in  the  last  rod  at 
the  cavo-surface  angle  being  a  full  length  rod,  supported  by  short- 
ened rods.  The  shortened  enamel  rods  are  covered  with  the  fill- 
ing material  \\lien  the  completed  filling  is  in  position. 

This  is  accomplished  by  a  slight  planing  motion  parallel  to  the 
external  enamel  line,  using  a  keen-edged  chisel  or  enamel  hatchet. 
The  gingival  margin  trimmers  are  especially  adapted  for  this  pur- 
pose Avheu  finishing  the  margins  in  the  gingival  third. 

The  Marginal  Bevel  should  be  laid  in  a  plane  at  an  angle  of  from 
six  to  ten  centi'igrade  degrees  from  the  plane  of  the  enamel  cleav- 
age. 

The  Depth  of  the  Marginal  Bevel  sliould  generally  not  include 
more  thaji  one-fourth  of  the  enamel  wall,  but  when  making  a  fill- 
ing of  inferior  edge  strength,  as  amalgam,  porcelain,  cement,  etc., 
it  becomes  necessary  to  bury  the  bevel  angle  more  deeply. 

Locations  subject  to  great  stress  also  require  the  placing  of  the 
bevel  angle  more  deeply,  even  carrying  it  beyond  the  enamel- and 
laying  it  in  the  dentine. 

Toilet  of  the  Cavity. 

Definition.  The  toilet  of  the  cavity  is  Hie  final  stcj)  in  the  prep- 
aration of  the  cavity  and  consists  of  freeing  the  cavity  of  all  loose 
particles  of  tooth  substance  whicli  arc  not  fiiinlx  attached  to  the 
<'avity  walls. 

This  is  best  accomplished  l)\-  a  blast  of  air  from  llic  clii])  blowei-, 
follr)wed  hy  a  tliof(»n<rli  swe('|)ing  and   hrnsliinu'  of  all  snrfaces  witli 


46  OPERATIVE   DENTISTRY 

cotton  or  spunk  held  in  the  pliers,  and  again  using  the  chip  blower 
to  remove  dust. 

White  Enamel  Margins  indicate  the  presence  of  loosened  enamel 
rods.  If  the  sweeping  does  not  remove  this,  the  margins  should  be 
again  chiseled,  using  a  keen-edged  instrument  and  a  light  hand, 
then  again  be  swept  Avith  cotton. 

If  the  whitened  margin  still  persists,  it  should  be  brushed  over 
with  an  extra  tine  cuttle-fish  disk  or  strip  when  the  loosened  rods 
Avill  be  carried  away.  The  margin  should  be  planed  again  with 
the  chisel. 

Care  in  the  Use  of  Disk  or  Strip.  It  should  be  fully  understood 
that  when  a  disk  or  strip  is  used  for  this  purpose,  the  grit  must 
be  so  fine  that  there  is  no  considerable  cutting  done,  as  there  is 
danger  of  changing  the  relation  of  the  bevel  to  the  enamel  cleav- 
age. 

All  Fluids  Should  be  Used  Previous  to  Cavity  Toilet.  The  habit 
of  swabbing  out  cavities  with  alcohol  or  other  substances  after  cav- 
ity toilet  is  useless,  and  may  do  harm  by  introducing  substances 
with  the  liquid  not  easily  removed. 

Disinfection  and  Pulp  Protection  should  have  consideration  fol- 
lowing the  removal  of  remaining  decay  and  as  a  preliminary  step 
in  toilet  of  the  cavity. 

If  a  fixed  oil,  or  an  essential  oil  which  may  contain  impurities 
has  been  used,  free  swabbing  and  scrubbing  of  the  walls  with  al- 
cohol, or  sulphuric  ether,  is  advised  for  cleansing  purposes,  to  get 
rid  of  the  oil  and  other  residue.  However,  simply  wiping  the  cav- 
ity out  will  not  suffice.  It  must  be  thoroughly  rubbed  with  an  al- 
cohol or  ether-moistened  cotton  ball,  followed  by  reasonable  desic- 
cation from  the  chip  blower,  and  then  every  part  of  the  walls  and 
margins  gone  over  and  freshly  cut.  This  is  the  only  means  of  ob- 
taining a  clean  surface. 

Leaks  in  Rubber  Dam,  particularly  near  the  gingival  outline, 
must  positively  be  detected.  The  portion  which  has  become  wet 
should  be  dried  with  an  absorbent  and  the  air  blast.  Then  all  parts 
which  have  been  moistened  must  be  gone  over  and  freshly  cut. 
Simply  drying  such  portions  is  not  adequate,  as  there  is  left  salts 
and  albuminoids  from  the  saliva  and  blood  serum  which  can  only 
be  removed  by  the  cutting  instruments.  The  placing  of  a  filling 
over  this  gummy  residue  invites  secondary  caries.  These  deposits 
will  subsequently  dissolve  out,  resulting  in  a  leak.    It  may  be  small 


TOILET    OF    THE    CAVITY  47 

but  the  acid  of  tooth  decay  will  easily  exchange  places  with  such 
films. 

If  the  cleaning  has  been  fairly  well  done,  it  may  result  only  in 
Avhat  is  termed  "blue  margin." 

When  time  intervenes  lietween  cavity  preparation  and  the  mak- 
ing of  the  tilling,  as  from  one  sitting  to  another,  the  walls  and  mar- 
gins should  be  retrimmed  to  give  fresh  cut  sui-faces  to  fill  against. 
This  is  not  possible  in  the  making  of  inlays  as  to  retrim  the  mar- 
gins destroys  the  fit.  The  fact  that  many  times  we  cannot  place 
the  inlays  against  surfaces  which  have  been  freshly  cut  constitutes 
the  greatest  enemy  to  their  permanence. 

It  is  the  one  great  argument  that  inlays  should  be  made  at  one 
sitting  and  under  dry  conditions. 

Conclusion.  All  fillings  should  be  made  against  clean,  freshly 
cut  walls. 


CHAPTER  X. 

MANAGEMENT  OF  PIT  AND  FISSURE  CAVITIES. 

(CLASS  ONE.) 

Location.  Class  One  cavities  occur  in  the  occlusal  surfaces  of 
molars  and  bicuspids ;  in  the  middle  and  occlusal  thirds  of  the  buc- 
cal and  lingual  surfaces  of  molars  and  in  the  lingual  surfaces  of 
incisors,  more  frequently  in  the  laterals.      (See  Figs.  1  and  2.) 

The  Predisposing-  Cause  of  decay  in  these  localities  is  a  fault  in 
the  enamel  due  to  imperfect  closure  of  the  enamel  plates,  affording 
a  convenient  point  for  the  lodgment  of  food  particles  and  the  ac- 
tive principles  of  fermentation  which  is  the  exciting  cause  of  all 
tooth  decay. 

Extension  for  Prevention  is  Seldom  Necessary  in  this  class  of 
cavities  from  the  fact  that  the  surface  of  the  enamel  in  the  immedi- 
ate neighborhood  is  exposed  to  the  friction  of  mastication.  It  is 
only  necessary  to  cut  away  the  enamel  walls  sufficiently  to  uncover 
the  area  of  affected  dentine,  and  to  include  in  the  cavity  outline 
all  sharp  grooves  connected  with  seat  of  primary  decay  to  a  loca- 
tion that  will  permit  a  smooth  finish  to  the  surface  of  the  filling 
and  an  outline  void  of  angles. 

Tendency  to  Extensive  Dentinal  Decay  must  be  remembered  in 
dealing  with  this  class  of  cavities  as  the  merest  opening  through 
the  enamel  Avill  frequently,  upon  excavation,  show  an  extensive  loss 
of  dentine. 

Incipient  Decays  in  Occlusal  Defects. 

Description.  Upon  examination  it  is  found  that  the  tine  of  a 
sharp  explorer  will  pass  between  the  non-united  plates  of  enamel 
to  the  depth  of  the  entire  thickness  of  enamel  in  one  or  more  points. 
A  more  careful  examination  may  show  the  surface  of  the  dentine 
to  be  softened  to  a  greater  or  less  extent  immediately  pulp-wise 
from  the  enamel  fault.     Such  cases  demand  immediate  attention. 

Outline  Form.  To  open  such  cavities  there  is  placed  in  the  en- 
gine a  discarded  No.  I/2  or  1  round  bur  which  has  been  made  into 
a  spade  drill  by  flattening  on  two  sides.  This  drill  is  made  to 
travel  between  the  plates  of  the  enamel  through  a  major  portion 
of  the  defect,  which  results  in  widening  the  fissure.  This  prelimi- 
nary step  will  result  in  much  saving  of  burs,  as  a  bur  which  has 
been  once  used  on  an  enamel  wall  is  unfitted  to  cut  dentine.     The 

48 


PIT   AND   FISSUKE    CAVITIES  49 

oommon  practice  of  using  dentate  fissure  burs  for  this  work  is  con- 
sidered as  brutal  to  the  patient  and  is  a  thief  of  the  operator's 
time.  A  No.  lo  or  1  round  bur  is  now  used  in  the  engine  and  ap- 
plied to  the  dentine.  By  swaying  the  hand  piece  to  and  fro  the 
dentine  is  cut  away  from  beneath  the  enamel  walls.  The  bur  should 
be  frequently  removed  to  allow  of  cooling  as  heat  readily  develops 
and  is  a  great  and  frequent  source  of  pain  to  the  patient. 

The  Use  of  the  Chisel  is  next  advised  for  the  removal  of  the 
overhanging  enamel  Avail;  first,  because  this  is  the  easiest  and 
speediest  means  of  its  accomplishment,  and  second,  because  this  is 
the  only  means  of  securing  the  cleavage  of  the  enamel,  giving  the 
operator  the  opportunity  to  judge  the  amount  of  resistance  to 
stress  in  the  several  localities,  and  to  learn  of  the  direction  of  the 
enamel  rods.  Many  times  a  chisel-edged  hatchet  will  be  most  ad- 
vantageous, one  which  has  a  chisel  edge  upon  the  sides  of  the 
blade  as  well  as  the  cutting  edge.  The  size  should  be  governed  by 
the  size  of  the  opening  secured,  but  in  every  ease  as  large  an  in- 
strument as  the  orifice  will  admit  should  be  used.  This  process 
should  l)e  repeated  with  bur  for  cutting  dentine  and  chisel  or 
hatchet  for  cleaving  enamel  until  the  desired  cavity  outline  is  ob- 
tained. 

Resistance  Form.  The  operator  should  include  all  fissure  and 
sulcate  grooves.  Cross  all  grooves  and  ridges  at  as  near  a  right 
angle  as  possible.  Avoid  eminences  of  primary  calcification.  Lay 
the  outline  as  much  as  possible  along  the  sloping  sides  of  the  tri- 
angles and  ridges,  as  these  are  the  most  favored  localities  for  a 
cavity  margin,  for  on  these  sloping  surfaces  we  find  the  greatest 
amount  of  friction  during  the  process  of  mastication,  due  to  the 
excursions  of  food,  and  they  are  the  least  exposed  to  direct  stress, 
as  the  ])]ows  are  of  glancing  nature. 

Retention  Form.  Ilei-e  is  a  good  rule  to  follow  in  cavities  of 
Class  One.  When  the  depth  of  the  cavity  is  equal  to  or  grea.ter 
than  the  width,  parallel  walls  ai-e  sufficient.  But  when  the  Avidth 
exceeds  the  depth  the  external  Avails  should  meet  the  internal  Avail 
at  a  .slightly  acute  angle.  These  angles  are  best  made  acute  by  the 
use  of  a  chisel-edged  hatchet  or  hoe,  having  corners  that  are  slight- 
ly acute.  With  a  ])laiiiiig  motion  they  should  be  made  to  travel 
parallel  with  the  base  line  angles.  This  Avill,  at  the  same  time, 
flatten  the  seat  or  pulpal  wall.  The  exti-cme  ends  of  long  arms  in 
a  filling,  such  as  results  fi'om  following  a  slcndci-  fissure,  must  be 
made  retentive. 


50 


OPERATIVE    DENTISTRY 


Convenience  Form.  No  convenience  form  is  usually  necessary 
in  small  cavities  Class  One,  except  in  rare  instances  it  may  be  of 
advantage  to  sharpen  one  of  the  distant  point  angles  to  facilitate 
the  starting  of  a  cohesive  gold  filling.  But  usually  the  first  por- 
tion of  gold  may  be  used  of  sufficient  size  to  entirely  cover  the 
pulpal  wall,  in  which  case  it  can  be  securely  locked  to  position  be- 
tween the  surrounding  avails. 

Removal  of  Remaining  Decay.    By  this  time  the  carious  dentine 


Fig.    17. — Complex   Class   One  cavity   prepared. 

will  usually  have  been  removed.  Should  any  remain  it  should  be 
excavated  with  suitable  spoons. 

At  this  point  there  should  be  a  thorough  inspection  of  the  dento- 
enamel  junction  for  small  areas  of  softened  dentine  which  may 
have  escaped  notice. 

The  Walls  should  all  be  flat,  particularly  the  pulpal.  In  cases 
where  decay  has  progressed  so  deeply  into  the  dentine  that  to  flat- 
ten the  pulpal  wall  would  cause  the  involvement  of  the  recessional 
tracts  of  the  horns  of  the  pulp,  the  base-line  angle  should  be  made 
intermittent,  omitting  the  squaring  of  the  angles  in  the  regions  of 
the  recessional  tracts. 

Disinfection.  The  cavity  should  be  flooded  with  alcohol  carry- 
ing a  small  per  cent  of  formaldehyde,  say  one  or  one-half  per  cent, 
and  evaporated  to  dryness. 

Finish  of  Enamel  Walls.    The  enamel  wall  should  be  planed  for 


PIT   AND   FISSURE    CAVITIES 


51 


the  entire  outline  of  the  cavity  with  a  sharp  chisel  using  a  light 
hand :  the  desired  cavo-surface  angle  secured,  and  the  bevel  angle 
buried  to  the  desired  depth.  The  movement  of  the  chisel  should 
parallel  the  travel  of  the  external  enamel  line. 

Toilet  of  the  Cavity.  The  cavity  should  he  swept  Avith  a  tightly 
rolled  cotton  l)all  or  piece  of  spunk  in  the  pliers  and  the  dust  finally 
removed  Avith  a  blast  of  air  from  the  chip-blower,  and  the  filling 
immediately  placed. 


Fig.   18. — Class  One  filled.      Cavity  shown  in  Fig.    17. 

Inlays.  If  the  cavity  is  to  be  occupied  by  an  inlay,  retention 
form  may  have  been  omitted  and  applied  to  the  cavity  just  be- 
fore setting  the  filling,  in  Avhich  case  the  toilet  of  the  cavity  should 
be  repeated.  If  the  cavity  has  already  been  given  retention  form 
the  same  should  be  temporarily  remoA-ed  while  making  the  model 
by  wiping  into  the  retaining  angles  wax,  temporary  stopping,  or 
cement  to  be  removed  before  final  placing  of  the  filling. 


CHAPTER  XI. 

MANAGEMENT  OF  PIT  AND  FISSURE   CAVITIES.      (CLASS 
ONE  CONCLUDED.) 

Large  Cavities  in  Central  Fossa  of  Molars. 

Description.  Such  cavities  are  usually  the  result  of  knowing- 
neglect  on  the  part  of  the  patient.  HoAvever,  in  cases  where  the 
enamel  is  strong  and  of  a  good  resistant  quality,  or  the  teeth  are 
so  occluded  as  to  have  received  little  stress,  the  patient  may  be  in 
ignorance  of  the  great  havoc  which  has  been  done,  due  to  the 
major  portion  of  the  enamel  remaining  intact.  There  may  exist  in 
such  cases  only  the  slightest  aperture  through  a  defective  fissure 
or  fault  in  the  enamel. 

Outline  Form.  This  division  of  Class  One  should  be  opened  with 
a  straight  or  bin-angle  chisel  of  rather  large  size  to  prevent  easy 
passage  to  the  sensitive  pulpal  wall.  A  chisel  of  from  two  to 
three  millimeters  in  width  is  advised.  The  securing  of  adequate 
finger  rest  on  adjacent  tissues  is  important.  The  chisel  should  be 
applied  so  as  to  throw  the  chips  into  the  cavity,  and  the  mallet 
substituted  for  heavy  hand  pressure.  It  is  best  to  begin  on  mar- 
gins most  mesial  and  nearest  the  operator's  eyes,  as  this  increases 
the  range  of  vision  to  the  deeper  portions  of  the  cavity  at  an 
early  stage  in  the  procedure.  This  chipping  away  of  the  enamel 
should  be  continued  until  enamel  supported  by  sound  dentine  is 
reached  and  until  the  margins  have  been  carried  to  desired  regions 
as  set  forth  in  general  in  the  chapter  on  outline  form. 

When  Pulp  Exposure  is  Feared.  In  this  case  the  sixth  step  in 
cavity  preparation  will  come  in  third  and  we  have  for  considera- 
tion the  removal  of  remaining  decay. 

Up  to  this  point  only  the  most  superficial  examination  of  the  in- 
ternal surfaces  has  been  made. 

Placing'  the  Rubber  Dam  at  this  point  is  expedient  as  dryness  is 
imperative.  The  decay  is  now  removed  with  large  spoon  excava- 
tors, whose  blades  are  at  least  two  millimeters  wide.  These  spoons 
which  should  be  keen  of  edge  are  carefully  worked  under  the  edges 
of  the  masses  of  softened  dentine  and  by  a  prying,  sweeping  move- 
ment this  lifted  en  masse  from  the  walls.  The  blade  of  the  ex- 
cavator should  be  prevented  from  scraping,  or  sliding  over  the  re- 
gions of  suspected  exposure. 

52 


PIT   AXD   FISSURE    CAVITIES 


53 


When  the  Pulp  is  Exposed  or  nearly  so  tlie  operator  will  pro- 
ceed to  pulp  treatment,  of  either  devitalization  or  conservation, 
as  the  case  demands.  This  step  completed  outline  form  is  again 
taken  up  and  fissures  and  sulcate  grooves  included  in  the  cavity 
outline. 

Resistance  and  Retention  Forms.  xVs  to  resistance,  we  have  only 
to  consider  the  pr()l)able  stress  to  be  sustained  by  the  filling  as 
a  Avhole  and  of  the  margins  in  their  various  localities.  This  will 
involve  a  study  of  each  case  in  hand,  as  to  occlusion  and  articula- 
tion, as  well  as  to  hal)its  of  the  patient  in  mastication.  The  prob- 
lem of  concave  pulpal  wall   is  hei'e  met  in  its   most  exasperating 


A  B 

Fig.    19. — I^arge   Class  One   cavities   prcijarecl. 

form.  ]\rany  times  if  the  operator  were  to  take  the  lower  levels 
of  the  pulpal  wall  and  attempt  to  flatten  and  carry  this  wall  lat- 
erally until  it  could  be  made  1o  meet  sui-i'ounding  walls  at  different 
angles,  the  recessional  ti-acts  of  the  })ulp  would  be  crossed  and  ex- 
posui-e  of  that  organ  i-esult. 

The  Flattening  of  the  Pulpal  Walls  Avoided.  (See  Fig.  10.) 
This  lateral  cutlinu'  1o  Il;i1tcn  i)ulpal  walls  may  be  avoided  in  two 
ways : 

First.  The  operator  may  establisli  a  level  highei-  u])  on  the  lat- 
eral walls  for  the  creation  of  tlic  base  line  angles,  resulting  in 
steps.      These   steps   shoiibl    be    established    in    places    most    remote 


54 


OPERATIVE   DENTISTRY 


from  recessional  tracts,  which  will  generally  be  found  in  the  neigh- 
borhood of  developmental  grooves.  There  should  be  at  least  three 
of  the  steps  or  small  supplemental  seats.  Four  point  suspension  is 
better.  As  the  seats  are  small  and  will  probably  be  required  to 
carry  relatively  heavy  loads  their  angles  should  be  most  definite. 

Second.  To  avoid  the  flattening  of  these  pulpal  walls  in  large 
cavities  of  this  class  the  operator  should  build  the  metal  portion 
of  the  filling  immediately  into  cement  which  has  been  applied  to 
the  pulpal  wall.  This  renders  the  base  of  the  filling  adhesive  to  its 
seat  and  nullifies  the  tendency  of  the  filling  to  slip  or  revolve  under 
load. 

It  might  be  said  here  that  the  principle  of  the  inlay  is  marginal 


A  B 

Fig.   20. — Class  One  filled.      Cavities  shown  in   Fig.    19. 


ridge  introduced  into  a  built-in  filling,  a  much  valued  feature  by 
many  operators. 

Convenience  Form.  There  is  no  convenience  form  required  in 
this  class  of  cavities  when  making  a  plastic  filling.  In  the  making 
of  a  cohesive  gold  filling  in  this  division  of  cavities  care  must  be 
taken  that  the  mesial  wall  can  be  reached  by  direct  force  from  the 
plugger  point.  In  some  cases  it  will  be  required  to  move  the  mesial 
margin  well  upon  the  mesial  marginal  ridge  to  accomplish  the  de- 
sired result. 

Convenience  Point  for  the  beginning  of  the  first  pieces  of  gold 
should  be  obtained  through  the  use  of  a  small  quantity  of  thin  ce- 
ment applied  to  the  deepest  portions  of  the  cavity. 

Finish  of  Enamel  Walls  and  Toilet.    The  cavity  should  be  phenol- 


PIT    AND   FISSURE    CAVITIES 


55 


ized  and  the  same  evaporated  to  dryness.  The  entire  cavity  outline 
should  be  freshly  planed,  the  margins  slightly  beveled  and  a  posi- 
tively determined  eavo-surface  angle  established.  The  depth  the 
bevel  angle  is  to  be  buried  should  be  determined. 

The  cavity  should  be  thoroughly  swept  with  cotton,  the  dust  dis- 
sipated with  a  blast  from  the  chip  blower  and  the  filling  immedi- 
ately placed. 

Pit  Cavities  in  Buccal  and  Lingual  Surfaces  of  Molars. 

Description.  These  cavities  have  their  origin  in  defects  in  the 
enamel  on  the  buccal  surface  of  lower  molars  and  the  lingual  sur- 
face of  upper  molars. 

Instrumentation  is  the  same  for  the  same  class  and  size  of  cav- 


A  B 

Fig.  21. — Ungual  i)it  cavities. 

ities  just  described  on  the  occlusal  surface,  excepting  perhaps  it 
may  be  necessary  to  use  the  engine  burs  in  the  contra-angle  hand 
piece,  a  necessity  seldom  met  with  on  the  occlusal  surfaces. 

Outline  Form.  The  outline  should  be  carried  well  out  of  the 
pit  or  groove  and  sufficiently  extended  to  meet  the  general  rules 
given  in  the  chapter  on  this  subject. 

Resistance  Form  will  come  up  for  consideration  only  when  the 
outline  approaches  the  occlusal  marginal  ridge.  In  such  cases  if 
the  occlusal  wall  is  not  made  up  of  a  sufficient  bulk  of  dentine  to 
withstand  the  stress  of  mastication,  the  outline  should  be  carried 
over  the  marginal  ridge  to  the  occlusal  surface,  in  which  case  rules 
for  the  outline  of  this  portion  of  the  cavity  will  be  the  same  as  pre- 
viously given  anfl  applicable  to  all  cavities  invading  occlusal  surfaces. 


56 


OPERATIVE   DENTISTRY 


Extension  for  Prevention  will  come  in  for  consideration  when 
the  ontline  has  for  other  causes  been  brought  near  to  the  free 
margin  of  the  gum.  A  full  application  of  the  rule  ''Extension  for 
prevention"  would  demand  that  the  gingival  outline  be  carried 
under  the  free  margin  of  the  gum  when  the  gum  has  already  been 
approached  to  within  one  millimeter.  A  failure  to  extend  the  out- 
line is  permissible  in  mouths  kept  scrupulously  clean. 

Retention  Form.  This  step  is  very  simple  when  the  cavity  does 
not  involve  the  occlusal  surface  and  is  fully  obtained  when  the  in- 
ternal line  angles  have  been  well  squared.  However,  when  the 
cavity  reaches  the  occlusal  surface,  the  filling  is  subjected  to  the 
greatest  amount  of  tipping  strain  in  mastication.     These  will  then 


A  B 

Fig.  22. — Class  One  filled.     Cavities  shown  in  Fig.  21. 


demand  a  flat  gingival  wall,  and  in  some  cases  of  a  vital  tooth,  a 
flat  pulpal  w^all  placed  parallel  to  the  gingival  wall,  and  the  line 
angles  surrounding  these  walls  well  defined.  The  four  point  angles 
should  be  slightly  acute. 

Finish  of  Enamel  Walls.  In  the  management  of  these  axial  sur- 
face pit  and  fissure  cavities  the  varying  slant  of  the  enamel  rods 
should  not  be  lost  sight  of.  This  should  be  noted  when  outlining 
the  cavity  with  the  chisel.  The  rods  will  generally  be  found  to 
incline  toAvards  the  pit,  from  every  direction  close  to  the  defect, 
while  a  little  way  out  they  will  be  found  at  right  angles  to  the' 
surface. 

Going  farther  toward  both  the  occlusal  surface  and  gingival  line, 


PIT    AND   FISSURE    CAVITIES  57 

the  outer  eiiels  of  the  rods  will  be  found  to  incline  more  and  more 
away  from  the  seat  of  decay. 

These  facts  should  be  borne  in  mind  and  a  full  cleavage  ob- 
tained. 

There  now  remains  only  the  usual  marginal  l)evel  and  cavity 
toilet. 

Pit  Cavities  in  Lingual  Surfaces  of  Upper  Incisors. 

Should  Receive  Early  Attention.  These  cavities  should  be  de- 
tected in  their  early  stages  as  their  near  location  to  the  pulp  ren- 
ders pulp  complications  an  early  sequence. 

It  is  the  best  of  practice  to  permanently  fill  all  cases  presented 
Avhere  faults  in  enamel  are  diagnosed. 

Instnimentation.  Their  location  renders  excavation  hazardous. 
The  engine  bur  should  be  used  for  superficial  opening  only,  the 
most  of  the  preparation  being  done  with  hand  instruments. 

Outline  Form.  The  general  rules  in  outline  form  should  be  ob- 
served. Particular  note  should  be  made  of  the  extreme  incisal  in- 
clination of  the  outer  ends  of  the  enamel  rods  along  the  margin 
of  the   incisal  Avail. 

Inciso-Axial  Line  Angle.  It  is  generally  advisable  to  alloAv  the 
incisal  wall  to  meet  the  axial  at  quite  an  obtuse  angle,  in  some 
cases  almost  to  the  ol)literation  of  this  line  angle,  as  the  squaring 
of  this  angle  will  greatly  endanger  the  pulp. 


CHAPTER  XII. 

MANAGEMENT  OF  PEOXIMAL  CAVITIES  IN  BICUSPIDS  AND 
MOLARS.     (CLASS  TWO.) 

Location.  Class  Two  cavities  are  those  which,  originate  on  the 
proximal  surfaces  of  molars  and  bicuspids  at  a  point  slightly  gin- 
gival from  the  point  of  contact. 

Predisposing  Cause.  The  predisposing  cause  is  the  fact  of  the 
presence  of  the  adjoining  tooth  which  establishes  and  maintains 
the  sheltered  position  for  the  accumulation  of  substances  which  un- 
dergo fermentative  decomposition. 

Early  Detection  of  These  Cavities  is  Essential.  It  is  of  the  ut- 
most importance  that  Class  Two  cavities  be  discovered  early.  More 
pulps  are  lost  to  the  teeth  from  the  neglect  of  these  cavities  than 
from  any  other  cause.  Their  early  detection  is  by  no  means  an 
easy  matter  to  the  inexperienced  operator,  as  often  their  presence 
is  shown  only  by  a  change  in  the  color  of  the  overlying  enamel. 

There  are  yet  other  cases  where  the  teeth  must  be  separated  for 
an  examination  of  the  suspected  surfaces. 

It  requires  education  in  the  use  of  the  explorer  to  detect  the  dif- 
ference in  the  ''feel"  of  the  explorer  tine  in  the  proximal  space 
and  the  entry  of  the  point  into  a  cavity  of  slight  depth.  When! 
the  decay  has  extended  along  the  dento-enamel  junction  the  case 
becomes  much  easier  and  should  never  escape  the  detection  of  the 
operator. 

Small  Proximal  Cavities  (Class  Two). 

Description.  By  examination  there  is  found  to  be  established 
an  area  of  decay  upon  the  enamel  surface  between  contact  point 
and  the  free  margin  of  the  gum,  or  one  or  both  teeth  which  go, 
to  form  the  space  in  question.  The  dentine  may  or  may  not  be 
involved.  The  marginal  ridge  is  yet  intact  and  firm.  The  enamel 
shows  no  signs  of  injury  in  either  the  buccal  or  lingual  embrasures. 
(Molar,  Fig.  3.) 

Gaining  Access.  Opening  the  cavity  is  often  the  most  difficult 
step  in  the  procedure. 

There  are  three  plans  of  procedure  open  to  the  operator. 

The  First  Method.  The  one  most  common  and  often  the  best 
is  to  place  the  angle  of  a  sharp,  straight  chisel,  say  one  milli- 
meter in  width,  on  the  proximal  slope  of  the  marginal  ridge  and 
tap  it  lightly  with  a  mallet ;  turn  the  other  angle  so  that  the  chisel 

58 


PROXIMAL    CAVITIES    IX    BICUSPIDS   AXD    MOLARS  59 

edge  rests  at  forty-five  degrees  to  the  position  of  first  impact  and 
again  apply  the  mallet.  Repeat  several  times  and  this  will  gen- 
erally' break  away  the  enamel  rods  in  a  small  V-shaped  space.  This 
may  be  continued  until  the  cavity  is  completely  uncovered.  In 
comparatively  resistant  cases  the  bi-bevel  drill  may  be  applied  to 
break  in  the  enamel. 

The  Second  Method  of  procedure  is  to  use  the  bi-bevel  drill  in 
the  mesial  or  distal  pit,  giving  the  hand  piece  that  slant  which 
will  cause  the  drill  to  enter  the  area  of  decay,  when  sufficient  depth 
has  been  reached.  The  chisel  is  then  applied  and  the  occlusal  sur- 
face enamel  cleaved  away  either  by  hand  pressure  or  the  mallet. 
This  method  is  more  liable  to  cause  pain  than  the  first  given  and 
should  be  used  Avith  caution. 

The  Third  Method  is  to  adjust  the  mechanical  separator  and  at- 
tack the  enamel  Avith  a  small  chisel  from  the  buccal  direction,  grad- 
ually shifting  more  and  more  to  the  occlusal  surface  until  finally 
the  enamel  ridge  gives  way  to  the  force  of  the  chisel. 

Preliminary  Separation  should  in  most  cases  be  resorted  to  for 
proper  access  for  the  many  reasons  set  forth  in  Chapter  IV. 

This  is  Best  Accomplished  by  packing  the  cavity  at  this  stage 
with  gutta-percha  for  a  few  days  or  weeks.  When  case  returns  we 
should  be  ready  to  consider  outline  form. 

Outline  Form.  Outline  form  in  Class  Two  involves  the  outlin- 
ing of  the  cavity  proper,  as  Avell  as  the  outlining  of  the  occlusal 
step  which  is  generally  necessary  because  of  the  more  secure  seat- 
ing and  rigidity  it  gives  a  filling  in  all  proximo-occlusal  cavities  in 
molars  and  bicuspids  Avhen  the  marginal  ridge  has  been  broken. 

Step  May  be  Omitted.  First:  In  cases  which  are  to  remain 
periiiaiieiitly  disaiticuhited,  as  when  opposing  tooth  has  been  lost. 

Second:  When  the  proximating  tooth  is  to  be  absent  permanently 
thus  obviating  much  cutting  buccally  and  lingually  in  extension 
for  prevention,  as  the  remaining  walls  are  sometimes  strong  enough 
to  give  sufficient  resistance  form  without  the  added  step. 

Third:  In  proximal  decays  in  the  gingival  third  following  ex- 
cessive gum  recession   (so-called  senile  decay). 

Fourth:  When  for  any  reason  the  patient  should  be  shielded  from 
long  operations,  or  the  life  expectancy  of  either  the  patient  or  the 
individual  tooth  is  short. 

Fifth:  In  that  form  of  lower  bicuspids  with  a  well  defined  and 
perfect  transverse  ridge.     (Fig.  23.) 

Outline  of  Cavity  Proper.     Tlic  oulline  should  be  carried  into 


60 


OPERATIVE    DENTISTRY 


both  buccal  and  lingual  embrasures  until  the  excursions  of  food 
through  these  embrasures  will  sweep  the  margins  of  the  completed 
filling  for  its  entire  length.  This  extension  will  result  in  carrying 
the  outline  out  sufficiently  that  it  can  be  seen  to  pass  under  the  gum 
in  full  view. 

A  Good  Rule  to  Follow  is  to  cut  sufficiently  that  a  chisel  one 
millimeter  in  width  will  pass  easily  from  the  embrasures  to  the 
open  cavity  when  dragging  the  cutting  edge  lightly  over  the  free 
margin  of  the  gum.  This  is  stated  as  a  general  rule  only,  there 
being  circumstances  which  Avould  permit  falling  short  of  this  amount 
of  space  and  yet  there  are  cases  which  demand  a  greater  amount 
of  cutting  to  fully  meet  the  requirements  of  extension  for  preven- 
tion, due  to  oral  conditions  and  dental  irregularities. 


A  B 

Fig.  23. — One  of  the  few  cases  in  which  the  step  may  be  omitted  in  Class  Two  cavities. 


Extensions  Gingivally.  The  cavity  outline  should  be  carried  sub- 
gingivally  in  extension  for  prevention  when  from  other  reasons 
that  part  of  the  outline  approaches  to  within  one  millimeter  of  the 
gum  line.  The  application  of  this  rule  will  invariably  cause  the 
outline  to  go  beneath  the  gum  in  case  the  gum  is  in  or  resumes  its 
normal  position. 

If  there  is  reason  to  believe  that  it  will  return  to  its  normal 
position  this  fact  should  be  considered.  In  cases  of  permanent  re- 
cession it  is  better  to  stop  the  cavity  outline  midway  from  contact 
to  gum  line. 

Care  at  Axio-Gingival  Angles.  The  buccal  and  lingual  portions 
of  the  outline  should  be  carried  directly  gingivally  and  be  made 


PROXIMAL    CAVITIES    IN    BICUSPIDS    AND    MOLARS 


61 


to  join  the  gingival  portion  of  the  outline  ])y  the  use  of  a  seg- 
ment of  a  small  circle.  The  use  of  a  large  circle  here  is  a  most 
common  error.  Investigation  of  fillings  will  show  many  failures 
Avherein  a  large  circle  has  been  used  allowing  the  external  outline 
to  disappear  in  the  proximal  space  before  it  has  disappeared  be- 
neath the  gum. 

The  Gingival  Outline  should  be  a  straight  outline  except  in  well 
defined  and  high  gum  festoons,  when  it  may  be  made  convex  to  the 
occlusal  surface. 

Forming  the  Step.  Place  a  small  round  bur  or  spade  drill  against 
the  axial  wall  at  the  dento-enamel  junction,  immediately  below 
the  central  fissure  and  undermine  the  enamel  the  desired  distance 
in  the  direction  of  the  central  axial  line  of  the  tooth.  Here  apply 
all  of  the  rules  and  methods  of  procedure  given  in  the  formation 


A  B 

Fig.  24. — Class  Two  cavities  in  molar  and  bicuspid  suitalile  for  cohesive  gold  or  amalgam. 


of  a  simple  occlusal  caNity.  Also  renieiiiher  to  ap])ly  the  I'ules  as 
given  in  outline  for-in,  particularly  as  to  resistance  form. 

Area  Included.  In  addition  to  the  above  it  is  a  safe  rule  to  state 
that  the  step  portion  should  involve  the  central  third  of  the  oc- 
clusal surface  bucco-lingually. 

Avoid  all  Angles  in  outline.  Care  should  be  taken  A\'hen  us- 
ing the  step  thai  its  union  Avith  the  cavity  proper  does  not  show 
in  the  outline  l)y  an  angle  at  their  junction.  Also  when  not  us- 
ing the  step,  as  in  the  few  cases  cited,  cai-e  should  be  given  not  to 
allow  the  axio-buccal  and  axio-lingual  line  angles  to  meet  the  ex- 
ternal enamel  line  These  line  angles  should  he  stopped  before 
Ihey   apprr)ae}i   the   cnaiiicl    A\all. 


62 


OPERATIVE   DENTISTRY 


Resistance  and  Retention  Forms.  To  reacli  the  maximum  of 
these  forms  it  is  necessary  that  the  gingival  wall  be  flat  and  laid 
in  a  plane  at  right  angles  to  the  stress  of  mastication.  The  gingival 
wall  should  meet  the  axial  Avail  at  an  angle  slightly  acute. 

The  grooving  of  the  gingival  wall  is  condemned. 

The  Buccal  and  Lingual  Walls  should  be  flat,  parallel,  meet  the 
gingival  wall  at  least  at  right  angles,  and  meet  the  axial  wall  at 
definite  and  acute  angles. 

The  Axial  Wall  should  be  convex  to  the  proximal  and  meet  the 
pulpal  wall  in  a  rounded  pulpo-axial  line  angle. 

The  Pulpal  Wall  should  be  laid  parallel  to  the  same  plane  as 
the  gingival  Avail  and  slightly  broader  at  the  portion  most  dis- 
tant from  the  cavity  proper.     This  gives  a  pulpo-distal  or  pulpo- 


Fig.    25. — ClaSs   Two   filled.      Cavities   shown   in   Fig.    24. 

mesial  line  angle  of  a  little  greater  length  than  that  of  the  pulpo- 
axial  line  angle,  resulting  in  a  dovetailed  effect  that  is  most  ef- 
ficient. 

Line  Angles.  The  line  angles  should  be  squared  out  and  made 
definite  by  the  use  of  small  hatchets  and  hoes  of  suitable  shapes 
to  reach  the  desired  localities. 

The  gingivo-buccal  and  gingivo-lingual  line  angles  should  ex- 
tend from  their  corresponding  point  angles  to  the  dento-enamel 
junction.  The  axio-buccal  and  axio -lingual  line  angles  which  arise 
in  the  same  point  angles  should  travel  occlusally  one-third  to  one- 
half  the  height  of  the  axial  wall.  In  some  rare  cases  where  the 
pulpal  wall  is  Ioav  from  decay  these  line  angles  may  meet  the  axio- 


PROXIMAL    CAVITIES   IN    BICUSPIDS    AND    MOLARS 


63 


pulpal  line  angle.  A  failure  to  observe  this  rule  endangers  the 
pulp  through  a  liability  of  crossing  its  recessional  tracts. 

Convenience  Form.  In  the  making  of  a  cohesive  gold  filling  a 
convenience  point  for  the  retention  of  the  first  piece  of  gold  is 
desirable.  This  is  best  accomplished  by  employing  a  small  in- 
verted cone  bur,  say  number  thirty-three  and  one-half. 

The  flat  face  is  placed  on  the  gingival  wall  and  first  sunk  to  one- 
third  its  depth  then  drawn  for  a  short  distance  occlusally  along" 
the  axial  line  angle,  taking  dentine  slightly  at  the  expense  of  both 
axial  and  external  walls. 


A  B 

Fig.  26. — Fillings  shown  in  Fig.  25  contacted,  illustrating  the  marble  contact. 

With  the  making  of  a  plastic  filling  there  is  no  need  of  cutting 
for  convenience  form  in  this  cavity. 

Inlays.  When  using  an  inlay  proper  convenience  form  is  ob- 
tained by  thorough  separation  and  causing  the  external  walls  of 
both  step  and  cavity  proper  to  meet  the  gingival  and  pulpal  wall 
at  slightly  obtuse  angles.     This  will  give  draw  to  the  occlusal. 

Finish  of  Enamel  Walls.  The  enamel  walls  are  planed  to  full 
cleavage  and  the  margins  arc  slightly  beveled.  All  but  the  gingival 
margins  may  be  done  with  the  chisel.  Special  instruments  are  re- 
quired to  bevel  the  gingival  cavo-surface  angle,  known  as  gingival 
marginal  trimmers.  These  are  made  rights  and  lefts  for  mesial 
cavities,  and  riglits  and  lefts  for  distal  cavities  and  should  be  on 


64  OPERATIVE   DENTISTRY 

hand  in  two  sizes,  Avhicli  Avould  result  in  eight  instruments  in  a 
good  working  set. 

In  planing  the  gingival  enamel  wall  the  operator  should  have 
in  mind  the  gingival  inclination  of  the  enamel  rods  in  this  locality. 

Toilet  of  the  Cavity  should  now  be  made  and  the  filling  immedi- 
ately placed. 


CHAPTER  XIII. 

LARGE   PROXIMAL   CAVITIES   ENDANGERING    THE   PULP. 
(CLASS  TWO,  CONTINUED.) 

Description.  This  class  of  cavities  Mhen  presented  show  exten- 
sive loss  of  dentine  in  the  proximal  wall.  The  marginal  ridge  may 
be  standing  or  it  may  have  been  broken  through  stress  of  mastica- 
tion. In  some  cases  there  may  be  an  occlusal  decay  in  the  central 
fossa. 

Danger  of  Pulp  Exposure.  There  is  ahvays  great  danger  of  pulp 
exposure  in  these  cases  and  this  fact  must  be  continually  borne  in 
mind,  during  the  procedure  of  preparation.  The  liability  is  in- 
creased -when  the  patient  is  young  or  the  cusps  of  the  tooth  are 
high,  particularly  when  there  exists  a  deep  pit  cavity  in  the  oc- 
clusal surface  necessitating  a  low  pulpal  Avail.  With  young  pa- 
tients the  pulps  are  large  and  the  horns  of  the  pulp  generally  ex- 
tend well  toward  the  cusps.  Teeth  with  high,  prominent  cusps  us- 
ually have  long  pulp  horns,  Avhich  should  be  considered  in  making 
resistance,  retention  and  convenience  forms. 

Outline  Form.  The  first  cuts  in  this  class  of  cavities  should  be 
Avith  the  chisel,  using  hand  pressure,  being  sure  that  adequate  hand 
and  finger  guard  has  been  obtained.  This  precaution  is  essential 
as  the  chisel  must  be  prevented  fi-om  reaching  the  sensitive  soft- 
ened dentine  Avithin  the  cavity.  Place  the  chisel  so  as  to  throAv 
the  chips  into  the  cavity.  The  chisel  should  be  made  to  engage 
only  a  small  portion  of  enamel  at  each  cut.  Should  the  enamel 
proA-e  resistant  the  aid  of  the  mallei  may  l)e  resorted  to,  still  main- 
taining a  firm  finger  rest. 

Extension  for  Prevention  is  fi-equently  not  necessary  as  the  ex- 
tension necessai-y  for  pi-oper-  resistance  form  Avill  carry  the  cavity 
the  required  distance  into  l)otli  l)uceal  and  lingual  embrasures. 
HoAvever,  in  many  cases  the  deca>-  will  be  found  to  haA^e  progressed 
more  toward  one  embrasure  than  the  otliei-  Avhich  necessitates  ad- 
ditional cntting  foi-  pi-evention,  in  the  direction  of  the  embrasure 
least  apj)roached  by  decay.  This  should  be  done  to  the  fnlfillment 
of  the  I'ule  for  "extension  fo?-  prevention." 

Gingival  Outline.  The  gingival  onllinc  in  these  eases  Avill  gen- 
erally be  under  the  free  margin  of  the  gnm.  At  this  stage  it  should 
be  planed  Avith  the  enamel  hatchets  until  the  overhanging  enamel 

65 


66  OPERATIVE   DENTISTRY 

is  broken  away  to  give  access  form  for  the  free  passage  of  the  dam 
and  ligature,  which  should  now  be  placed  and  the  cavity  super- 
ficially sterilized. 

Occlusal  Outline.  When  the  cavity  has  been  rendered  dry  the 
occlusal  outline  should  be  proceeded  with.  This  is  carried  out  as 
previously  given  in  the  forming  of  the  step  portion,  and  the  full 
satisfaction  of  the  rules  given  in  Outline  Form,  Chapter  V. 

Removal  of  Remaining  Decay.  This  is  an  instance  where  the 
sixth  step  in  cavity  preparation  comes  in  third  and  should  now 
be  cautiously  proceeded  with. 

Technic.  Large  spoons  should  be  used.  The  softened  and  dis- 
colored dentine  should  be  lifted  from  its  position  with  as  little  pres- 
sure pulp-wise  as  possible.  If  exposure  exists  upon  its  removal,  pulp 
treatment  for  devitalization  and  removal  is  the  immediate  pro- 
cedure. If  exposure  does  not  exist  and  the  operator  has  reason 
to  believe  that  that  organ  is  healthy  the  pulpal  and  axial  walls 
should  be  lightly  scraped  with  large  spoon  excavators,  the  walls 
disinfected  with  the  favorite  drug,  then  dried,  phenolized  and  dried 
again,  the  latter  precaution  to  prevent  thermal  shock  to  the  pulp 
during  the  remaining  portion  of  cavity  preparation,  the  impera- 
tive necessity  for  which  is  shown  when  pain  is  induced  by  a  blast 
of  air  from  the  chip  blower. 

Resistance  and  Retention  Forms.  When  the  central  portion  of 
the  decay  is  found  to  be  deep  and  no  exposure  exists,  the  pulpal 
and  axial  walls  should  be  left  in  their  central  portions  much  as  de- 
cay has  left  them,  no  attempt  being  made  to  flatten  these  walls  on 
a  plane  of  their  greatest  depth  as  pulp  exposure  may  result.  The 
line  angles  surrounding  these  two  walls  should  be  established  on 
higher  levels. 

The  Gingival  Wall  should  be  made  flat  in  every  direction.  This 
is  accomplished  by  lowering  the  point  angles  root-wise  to  the  level 
of  the  central  portion. 

Convenience  Form.  Every  part  of  the  cavity  should  be  exam- 
ined to  see  that  it  is  accessible  to  direct  force  in  the  packing  of 
the  filling  and  a  convenience  point  cut  in  each  of  the  gingivo-axio- 
lingual  and  gingivo-axio-buccal  point  angles. 

Pulp  Protection.  The  cavity  should  be  flooded  with  an  efficient 
non-irritating  disinfectant,  dried,  phenolized  and  again  dried.  If 
the  pulp  is  in  danger  it  should  be  protected  as  described  in  Chap- 
ter XXXIV. 


LARGE    PROXIMAL    CAVITIES   ENDANGERING    PULP 


67 


Finish  of  Enamel  Walls. 

The  enamel  Avails  should  now  be  inspected,  corrected  for  com- 
plete cleavage  and  the  proper  cavo-surface  angle  established,  iis- 


Fig.  27. — Large  Class  Two  cavities  in  non-vital  teeth  restoring  part  of  the  occlusal  surface  for 
the  protection   of  weakened   walls. 


A  B 

Fig.  28. — Class  Two  filled.     Cavities  shown  in   Fig.  27. 


ing  for  this  a  keen-edged  cliiscl   and  a  light  hand  with  a  planing 
motion  parallel   witii  the  external  enamel  line. 

For  Toilet  of  the  Cavity  use  a  few  blasts  of  air  from  the  chip 


C8 


OPERATR^    DENTISTRY 


blower,  followed  with  a  thorough  brushing  with  a  ball  of  cotton 
and  more  air  blasts.     The  filling  should  be  immediately  placed. 

Large  Proximal  Cavities  in  Non- Vital  Teeth. 

In  the  management  of  this  class  of  cavities,  cutting  for  resistance 


Fig.  29. — Mesio-occluso-distal  (M.O.D.)  cavities  in  molar  ani  bicuspid,  vital  teeth.  Note 
that  the  occlusal  portion  of  the  cavities  does  not  show  any  retentive  form.  It  is  not  necessary 
to  undercut  these  walls  as  there  is  ample  retention  in  other  parts  of  the  cavity. 


A  B 

Fig.   30. — Mesio-occluso-distal   fillings.      Cavities  shown  in  Fig.   29. 

to  stress  reaches  the  maximum  and  outline  is  many  times  materially 
extended  for  this  purpose  alone. 

Outline  Form,  With  Molars.     All  decay  and  softened  dentine  is 
removed.      Often  this  will  leave  standing  an  entire   cusp  of  un- 


LARGE    PROXIMAL    CAVITIES    EXDAXGERIXG    PULP 


69 


supported  enamel  and  possibly  both  proximal  cusps  are  thus  un- 
supported. Ill  such  cases  a  thin-edged  carborundum  wheel  is  placed 
on  the  occlusal  and  this  surface  ground  away  for  one  or  two  milli- 
meters, extending  as  far  toward  the  central  axial  line  to  just  be- 


-^^^^^^H 

PH 

'^;i^H 

^ 

[  M 

i^^    1 

^l^HHi^l 

Fig.  31. — {A)  First  superior  molar,  non-vital,  restoring  the  lingual  cusps.     (B)   Second  superior 
bicuspid,  non-vital,  restoring  the  entire  occlusal  surface. 


A  B 

Fi^.   32. — Class  Two  filled.     Cavities  shown  in   Fig.   31. 

yoiid  the  (Miccal  or  lingual  groove,  or  bolh  when  l)()tli  cusps  are  to 
be  removed.  This  grinding  process  is  carried  to  a  greater  depth 
in  the  region  of  the  groove,  resulting  in  a  stej)  which  gives  the  fill- 
ing an  occlusal  surface  seating. 


70  OPERATIVE   DENTISTRY 

With  Bicuspids  this  buccal  or  lingual  outline  is  carried  past  th.e 
crest  of  the  cusp  involved  and  partially  down  the  opposite  slope. 
This  procedure  results  in  disarticulating  the  frail  enamel  w^all  and 
so  placing  the  metal  that  it  will  receive  the  force  of  mastication. 

In  Mesio-Disto-Occlusal  Cavities  in  both  bicuspids  and  molars, 
which  are  vital,  and  when  using  cohesive  gold  as  a  filling,  the  occlusal 
outline  should  include  all  of  the  middle  third  bucco-lingually.  It 
should  be  made  sufficiently  deep  to  remove  all  of  the  enamel  in  the 
central  fissure. 

For  cohesive  gold  the  buccal  and  lingual  walls  should  be  parallel 
and  without  retention  as  the  retentive  form  should  all  be  placed  low 
in  the  gingival  angles  of  both  mesial  and  distal  cavities. 

In  the  use  of  amalgam  the  outline  should  be  farther  extended  buc- 
co-lingually, to  include  about  one-half  of  each  of  the  buccal  and  lin- 
gual thirds.  Thus  two-thirds  of  the  occlusal  surface  bucco-lingually 
will  be  filling.  This  occlusal  portion  should  be  without  retentive 
form  with  the  buccal  and  lingual  walls  meeting  the  pulpal  wall  at 
angles  slightly  obtuse.  This  is  the  minimum  amount  of  extension 
for  favorable  vital  cases. 

In  Cases  of  Extreme  Frailty  the  entire  occlusal  surface  of  molars 
and  bicuspids  should  be  replaced  with  filling  of  at  least  one  milli- 
meter in  thickness.  With  upper  molars  and  bicuspids,  when  non- 
vital  and  very  frail  mesio-occluso-distal  cavities,  the  lingual  cusps 
should  be  removed  for  one  or  two  millimeters  and  replaced  with 
filling  material. 

Retention  Form  is  Completed  by  squaring  up  the  side  walls  and 
sub-pulpal  wall,  making  a  box  shape  of  the  pulp  chamber,  with 
fairly  definite  point  angles. 

Convenience  Form.  No  convenience  form  is  necessary  in  this 
class  of  cavities,  except  for  inlay  fillings,  which  will  be  considered 
later. 

Neglected  Access  Form.  In  cases  where  large  proximal  cavities 
are  of  long  standing  and  there  has  been  much  tipping  to  the  prox- 
imal of  one  or  both  teeth,  preliminary  separation  for  good  access 
is  essential.  Without  this  preliminary  step  complete  contour  res- 
toration and  proper  contact  is  impossible.  This  is  particularly  true 
when  the  cavity  is  in  the  mesial  of  the  first  molar.  Many  times 
the  second  bicuspid  will  seem  to  have  been  engulfed  within  the 
molar  cavity.  In  cases  where  preliminary  separation  for  obvious 
reasons  is  impossible,  the  evil  may  be  partly  overcome  by  the  free 
cutting  away  of  both  buccal  and  lingual  walls  until  the  filling  may 


LARGE    PROXIMAL    CAVITIES   ENDANGERING   PULP  71 

be  built  ill  with  a  proximal  surface  slightly  convex  to  the  prox- 
inial.  However,  this  is  but  a  makeshift  of  a  filling  and  the  result- 
ing proximal  space  will  ahvays  be  defective. 

Toilet  of  the  Cavity.  In  large  decays,  particularly  if  the  pulp 
has  been  removed,  there  is  more  or  less  danger  in  leaving  coatings 
of  various  materials  clinging  to  the  walls.  Care  should  be  taken 
that  the  walls  are  scrupulously  clean.  It  is  an  advantage  if  the 
cavity  be  scrubbed  with  solvents  for  the  suspected  coatings.  The 
cavity  should  then  be  dried,  the  enamel  walls  planed  and  the  cav- 
ity freed  of  all  debris. 

Over-desiccation.  Particular  care  should  be  had  not  to  use  ex- 
cess desiccation  in  pulpless  teeth  as  this  will  render  them  brittle 
and  easy  of  fracture  when  put  to  use. 


CHAPTER  XIV. 

MANAGEMENT  OF  PROXIMAL  CAVITIES  IN  INCISORS  AND 

CUSPIDS  NOT  INVOLVING  THE  ANGLE.     (CLASS 

THREE.) 

Definition.  Class  Three  cavities  are  those  in  the  proximal  of 
incisors  and  cuspids  where  it  is  not  necessary  to  restore  the  ineisal 
angle.  The  angle  may  be  allowed  to  remain  when  the  enamel  at 
the  angle  is  supported  by  sound  dentine  to  an  extent  which  will 
give  it  sufficient  resistance  to  prevent  fracture  under  stress  of 
mastication. 

General  Form  of  Class  Three.  Cavities  in  incisor  proximal  sur- 
faces differ  from  all  others  in  that  they  are  in  the  surface  of  teeth 
of  a  triangular  form  and  the  cavities  of  necessity  must  be  of  this 
form,  rather  than  the  typical  box  shape  in  the  other  classes  of 
cavities. 

Location  of  Primary  Decay.  The  location  of  primary  decay,  as 
with  all  contact  decay,  is  just  gingivally  from  contact  point.  This 
will  result,  as  a  rule,  in  the  seat  of  initial  decay  being  about  mid- 
way from  the  ineisal  edge  to  the  gingival  outline.  As  the  plates 
of  enamel,  both  labial  and  lingual,  are  quite  heavy  and  usually 
removed  from  direct  stress,  there  will  generally  be  considerable 
loss  of  dentine  while  the  enamel  walls  are  yet  intact.  The  decay 
may  be  apparently  small,  yet  reflected  light  by  the  use  of  mouth 
mirror  will  show  a  discoloration  of  a  well  defined  area.  The 
curved  tine  of  an  explorer  may  or  may  not  enter  from  either  the 
labial  or  lingual  embrasure. 

Opening  the  Cavity.  Bathe  the  surfaces  of  all  the  anterior  teeth 
in  that  jaw  with  water  to  free  them  of  micro-organisms  and  gummy 
material,  particularly  the  gingival  border,  and  apply  the  mechan- 
ical separator. 

Gaining  Access.  With  a  small  straight  chisel  of  about  one  milli- 
meter in  width  cut  away  the  enamel  edge,  throwing  the  chips  into 
the  cavity.  Adequate  finger  rest  must  be  secured  before  applying 
the  chisel  and  only  small  portions  of  enamel  engaged  at  each  ap- 
plication, as  a  failure  in  either  respect  may  result  in  checking  the 
j3namel  to  a  greater  extent  than  desired.  When  sufficient  entrance 
has  been  made  to  the  cavity  to  admit  the  instrument,  the  remain- 
ing enamel  margins  may  be  planed  from  this  direction  until  a  liga- 

72 


PROXIMAL    CAVITIES    IN    INCISORS    AND    CUSPIDS 


73 


tiire  Avill  pass  from  the  incisal  to  the  gingival  line.  Where  time 
Avill  permit  the  ease  should  be  packed  for  preliminary  separation 
as  described  in  Chapter  IV.  If  immediate  separation  and  filling  is 
to  be  practiced  the  rubber  dam  should  be  adjusted  and  the  me- 
chanical separator  placed  and  tightened  to  a  snug  pressure.  The 
separator  should  be  tightened  from  time  to  time  until  the  required 
separation  is  obtained.  The  approxi)nate  space  required  is  from 
one-half  to  one  millimeter  Avhere  only  one  cavity  exists  in  the  prox- 
imal, and  a  full  millimeter  in  cases  where  two  cavities  exist. 

Outline  Form.  As  these  cavities  are  located  in  the  most  exposed 
portion  of  the  mouth  esthetic  reasons  demand  as  little  cutting  as 
possible  consistent  with  the  demands  for  permanency.     However, 


ABC 

Fig.  33. — Class  Three  cavities  filled  so  that  the  entire  cavity  outline,  excepting  that  jior- 
tion  covered  by  gum  tissue,  is  in  full  view  of  the  operator.  The  gingival  portion  of  (B)  has 
been  cut  sufficiently  low  to  be  covered  by  gum  tissue. 


it  is  a  good  I'ule,  in  outlining  cavities  of  Class  Three,  to  extend  in 
all  directions  until  when  the  filling  is  completed,  the  entire  cavity 
outline  not  covered  with  gum  tissue,  is  in  full  view  of  the  operator. 
(Fig.  33.)  As  stated  before,  excessive  cutting  to  obtain  this  con- 
dition may  be  obviated  by  proper  separation. 

The  Gingival  Outline  should  be  carried  midway  l)etween  con- 
tact and  gum  line,  and  farther  extended  to  go  under  the  gum  Avhen 
it  approaches  to  within  one  millimeter  of  the  gum.  Great  care 
should  be  exercised  to  scpiai-o  out  both  labial  and  lingual  axio- 
gingival   angles,  carrying  tlicui   suffi('ientl\'   into   these  embi-asuT'es 


74  OPERATIVE   DENTISTRY 

that  the  cavity  margins  may  be  in  full  view  as  they  pass  under  the 
gum. 

The  Incisal  Outline  should  be  carried  incisally  until  the  margin 
of  the  filling  will  be  permanently  in  view,  with  a  space  sufficient 
to  admit  of  the  free  use  of  the  tooth  brush  on  the  margin.  This 
would,  in  many  instances,  carry  the  margin  beyond  the  incisal 
edge  and  make  a  Class  Four  cavity  and  is  only  avoided  by  separa- 
tion and  filling  of  the  cavity  to  a  slightly  excess  contour. 

The  Labial  Outline  should  be  carried  into  the  labial  embrasure 
until  the  margins  are  in  full  view.  The  enamel  should  be  split 
away  until  full  length  rods  are  obtained.  On  account  of  the  ex- 
posed location  of  these  cavities  the  esthetic  reasons  demand  as  lit- 
tle cutting  labially  as  possible.  As  this  margin  is  practically  re- 
moved from  the  stress  of  occlusion  it  is  not  essential  that  the  enamel 
be  supported  by  dentine  in  every  instance.  However,  care  should 
be  taken  that  the  rods  are  full  length  and  that  all  rods  are  re- 
moved where  there  has  been  a  backward  decay  as  shown  by  a 
whitened  powder-like  condition  at  their  dentinal  ends. 

Additional  Extension  for  esthetic  reasons  is  sometimes  required 
in  th^  labial  embrasure.  This  is  more  often  true  in  the  mesial  cavi- 
ties wherein  the  teeth  are  angular  in  form  and  present  surfaces 
that  are  quite  flat,  resulting  in  a  very  square  or  prominent  mesio- 
labial  angle.  In  such  cases  the  outline  should  be  carried  over  the 
angle  and  into  the  labial  surface,  that  the  metal  may  be  brought 
into  the  light,  otherwise  the  completed  filling  will  have  the  appear- 
ance of  a  decay  or  dark  spot  on  the  tooth. 

The  Lingual  Outline  must  be  carried  into  the  lingual  embrasure 
sufficiently  to  be  brought  into  full  view  in  all  cases. 

In  the  case  of  teeth  of  rounded  form  this  will  not  always  in- 
clude the  proximal  marginal  ridge.  In  teeth  of  a  squared  form 
and  prominent  lingual  ridges  the  marginal  ridges  should  be  in- 
cluded and  the  outline  carried  along  the  axial  slope  of  the  ridge. 
The  fact  that  many  cases  show  a  lingual  articulation  and  occlusion 
on  the  lingual  marginal  ridges  of  upper  incisors,  will  bring  de- 
mands for  including  within  the  cavity  the  major  portion  of  these 
ridges,  unless  supported  by  a  good  bulk  of  sound  dentine.  The 
failure  to  recognize  this  fact  on  the  part  of  many  operators  is  re- 
sponsible for  the  loss  of  a  large  per  cent  of  this  class  of  fillings. 

Resistance  Form.  No  special  resistance  form  other  than  that 
just  given  is  required  in  this  class  of  cavities. 

Retention  Form.  When  this  order  in  the  preparation  has  been 
reached  attention  should  be  directed  to  the  incisal  angle,  particu- 


PROXIMAL    CAVITIES   IN    INCISORS   AND    CUSPIDS 


75 


larly  in  the  larger  eavities,  as  eases  Avill  be  met  in  which  it  will 
be  found  necessary  to  remove  the  incisal  angle  to  secure  proper 
^'retention  form."  This  looking  to  the  incisal  first  will  decide 
this  point  early  in  the  procedure. 

The  Incisal  Line  Angle  should  meet  the  axial  wall  at  least  at 
a  right  angle.  In  eases  where  this  line  angle  is  short,  as  found  in 
shallow  cavities,  the  incisal  line  angle  should  meet  the  axial  wall 
at  a  slightly  acute  angle.  It  is  not  necessary  to  make  a  convenience 
angle  at  the  incisal  point  angle.     (Fig.  34.) 

The  bevel  angle  on  the  gingival  wall  becomes  the  fulcrum.  It 
is  only  necessary  that  the  distance  from  this  point  to  the  incisal 
point  angle  be  greater  than  that  from  the  same  point  on  the  gin- 


Fig.  34. — Drawing  to  illustrate  the  retention  at  the  incisal  angle  of  Class  Three  cavity. 
In  shallow  cavities  with  a  short  incisal  line  angle  as  d — b,  the  angle  at  b  should  be  acute. 
In  deeper  cavities  and  longer  incisal  line  angles  as  the  one  shown  at  d — c,  the  incisal  point 
angle  is  efficient  if  it  is  a  right  angle  and  may  even  be  obtuse.  In  the  illustration  shown 
the  filling  would  pivot  to  exit  at  a.  Dotted  lines  a — b  and  a — c  are  the  same  length  hence 
the  point  angles  of  the  two  fillings  would  describe  an  arc  of  the  same  circle  in  tipping  to  exit. 

gival  wall  to  the  most  external  portion  of  the  incisal  line  angle. 
The  more  shallow  the  cavity  in  Class  Three  the  more  acute  must 
be  the  incisal  point  angle. 

Other  Point  Angles.  The  gingivo-axio-labial  and  the  gingivo- 
axio-lingual  p(nnt  angles  are  now  carried  into  the  dentine  at  the 
expense  of  both  axial  and  external  Avails,  care  being  given  not  to 
groove  the  gingival  wall. 

Line  Angles.  Line  angles  are  made  with  small  hatchets  and  hoes 
of  suitable  sizes,  say,  one-third  to  one-half  millimeter  in  width,  Avith 
edges  that  are  keen  and  whose  corners  are  well  defined,  not  having 
been  rounded  through  careless  shai-pening  or  wear. 


76 


OPERATIVE   DENTISTRY 


The  Axio-Labial  Line  Angle  is  chased  and  sharpened  for  its  entire 
length,  making  it  particularly  definite  as  it  approaches  each  of  the 
point  angles. 

The  Axio-Lingual  Line  Angle  is  made  definite  for  one  millimeter 
in  each  direction  from  its  two  point  angles,  omitting  the  central  por- 


Fig.  35. — Class  Three  cavities  prepared  for  cohesive  gold.  While  the  cavity  in  the  cuspid 
(A)  restores  the  mesial  angle  the  shape  of  these  cavities  and  the  rules  governing  their  man- 
agement places  them  in  Class  Three. 


ABC 

Fig.  36. — Class  Three  filled.     Cavities  shovi^n  in  Fig.  35. 


tion,  as  this  precaution  will  give  added  resistance  form  to  the  lingual 
wall.     The  sharpening  of  these  line  angles  is  best  accomplished  by 
engaging  the  instrument  in  the  dentine  the  desired  distance  from 
the  point  angle  and  cutting  to  the  angle. 
The  Gingivo-Axial  Line  Angle  should  be  well  defined  to  make  the 


PROXIMAL    CAVITIES   IX    INCISORS    AND    CUSPIDS  77 

gingival  wall  meet  the  axial  at  a  definite  angle,  but  should  in  no  way 
be  a  ditch  or  groove. 

The  Gingivo-Labial  and  Gingivo-Lingiial  Line  Angles  should  be 
cut  aAvay  from  their  point  angles  out  to  and  end  at  the  dento-enamel 
junction.  As  the  general  form  of  the  cavity  is  that  of  a  triangle 
these  angles  will  always  be  acute. 

Gingival  Wall.  The  gingival  wall  should  be  flat  in  every  direc- 
tion. 

Axial  Wall.  The  axial  wall  should  be  left  as  decay  has  left  it  in 
the  central  portion  and  all  additional  cutting  should  tend  to  make  it 
take  on  the  form,  in  miniature,  of  the  surface  of  the  tooth  in  which 
the  decay  has  originated.  A  disregard  of  this  rule  will  endanger 
the  pulp,  Avhereas  if  the  axial  M-all  is  left  as  convex  as  possible  the 
pulp  has  all  ]')ossible  protection. 

Labial  and  Lingual  Walls.  These  walls  should  be,  as  far  as  pos- 
sible, of  the  same  thickness  for  their  entire  length,  which  will  re- 
sult in  their  inner  surfaces  being  of  the  same  contour  as  the  ex- 
ternal surface  of  the  tooth. 

Convenience  Form.  Ta\'o  convenience  points  are  advisable  in  this 
class  of  cavities,  cut  in  each  of  the  gingivo-axio-labial  and  the  gin- 
givo-axio-lingual  angles.  The  filling  should  l)e  begun  in  the  latter 
angle. 

Removal  of  Remaining  Decay.  At  this  point  inspect  the  dento- 
enaiiiel  junction  foi-  softened  dentine.  Also  the  entire  axial  wall 
should  be  scraped  with  large  spoons  for  the  i-emoval  of  the  last  of 
the  softened  dentine,  the  cavity  disinfected,  di'ied,  phenolized  and 
again  dried.     Pul])  ])i-otoctor  should  be  applied  when  indicated. 

Finish  of  Enamel  Walls.  The  enamel  Avails  should  be  planed  to 
full  cleavage,  with  suitable  insti-uments  of  chisel  edges,  not  forget- 
ting the  incisal  and  gingival  inclination  of  the  rods  of  these  loca- 
tions. Bevel  the  cavo-surface  angle,  give  the  cavity  its  toilet  and 
iiiiiiK'diatcly  ])laf'c  the  filling. 

In  Non- Vital  Cases.  When  the  axial  wall  has  been  lost  l^y  reason 
of  pulp  removal  the  entire  pulp  chamber  should  be  filled  Avith  ce- 
ment of  a  A'ery  light  yelloAv  color  or  even  a  Avhite  cement  may  be 
used.  In  extremely  frail  teeth  this  may  be  only  pai'tially  filled  and 
the  remaining  portion  used  for  retention. 


CHAPTER  XV. 

MANAGEMENT  OF  PROXIMAL  CAVITIES  IN  INCISORS  IN- 
VOLVING THE  ANGLE.     (CLASS  FOUR.) 

Definition.  Cavities  of  Class  Four  are  those  in  which  the  incisal 
angle  has  either  been  lost  or  can  not  be  safely  retained.  The  deci- 
sion as  to  its  restoration  is  of  most  vital  importance.  To  cnt  the 
angle  from  nearly  every  incisor  which  has  a  proximal  decay  is  little 
short  of  malpractice,  while  at  the  same  time  to  attempt  to  save  those 
not  wholly  and  adequately  supported  by  dentine  is  to  invite  many 
disastrous  failures. 

Conditions  Demanding  Frequent  Angle  Restoration.  First.  When 
contact  is  in  the  incisal  third.  In  such  cases  a  very  small  decay  will 
involve  all  of  the  dentine  toward  the  incisal  angle. 

Second.  Incisors  which  have  long  flat  proximal  surfaces.  Such 
teeth  will  show  a  line  of  decay  extending  gingivo-incisally  and  may 
entirely  weaken  the  incisal  angle  before  the  pulp  is  in  danger. 

Third.  The  pulp  may  be  involved  and  its  removal  materially 
lessens  the  resistance  of  supporting  dentine  at  the  angle. 

FourtJi.  The  angle  under  consideration  may  be  so  located  that  it 
is  frequently  required  to  stand  great  stress  in  service.  This  is  a 
point  which  must  not  be  overlooked  as  an  angle  which  stands  well 
exposed  must  bear  much  greater  and  more  often  repeated  force  than 
an  angle  which  does  not  occlude  or  can  not  be  brought  into  articula- 
tion. 

Difference  Between  Mesial  and  Distal  Surfaces.  The  above  four 
conditions  will  be  more  frequently  met  with  in  mesial  surfaces, 
hence  the  mesial  angles  are  in  greater  danger  and  more  often  re- 
quire restoration. 

Plans  of  Angle  Restoration.  There  are  four  general  plans  of  re- 
storing the  incisal  angle  which  are  worthy  of  consideration.  Many 
plans  have  been  advanced  from  time  to  time,  but  the  four  given 
below  seem  to  have  remained  in  favor. 

Retention  Form  in  Class  Four  Fillings.  With  each  of  the  plans 
presented  and  generally  practiced  the  effort  is  made  to  remove  or 
nullify  the  principle  of  the  lever. 

With  proximal  fillings  wherein  the  force  of  mastication  is  brought 
in  direct  contact  with  the  filling  the  principles  of  the  lever  must  be 
reckoned  with.  The  force  of  mastication  is  the  power,  the  filling  the 
lever,  the  anchorage  in  the  point  angles  the  load  and  the  point  on 

78 


PROXIMAL    CAVITIES   IN   INCISORS   INVOLVING   ANGLE 


79 


which  the  filling  would  most  likely  pivot  to  exit  the  fulcrum.  By  a 
study  of  the  case  we  find  we  must  deal  with  the  force  of  levers  of 
both  the  first  and  second  class. 

In  Fig.  37  we  have  an  illustration  of  a  Class  Four,  plan  one  filling 
wherein  the  principles  of  a  lever  of  the  second  class  are  fully  opera- 
tive. The  heavy  long  lines  a-h  represent  the  full  length  of  the 
lever.  The  short  heavy  lines  a-c  represent  that  part  of  the  lever 
which  is  the  Avorking  arm,  as  the  load  is  at  c.  That  we  may  study 
the  amount  of  anchorage  to  be  provided  for  at  the  incisal  angle,  (c), 
we  will  ignore  the  assistance  of  the  two  gingival  point  angles  and 
for  that  reason  they  have  not  been  shown  in  the  drawing.    We  here 


Fig.  37. — Drawings  to  illustrate  the  principle  of  the  lever  in  the  dislodgement  of  fillings  of  the 

fourth  class,  plan  one. 


have  a  lever  of  the  second  class  with  the  fulcrum  at  a,  the  load  at 
c  and  the  force  at  h. 

In  order  that  we  may  not  inject  into  the  problem  at  this  time  the 
principle  of  the  bent  lever  we  will  consider  that  by  the  lateral  move- 
ment of  the  mandible  the  force  is  applied  at  right  angles  to  the 
"lever-arm."  In  diagram  A,  Fig.  37,  the  working  arm  is  one-half 
of  the  lever  which  is  of  the  second  class.  We  then  have  the  follow- 
ing with  X  representing  the  load,  or  unknown  quantity: 

100  lbs.  :  X  : :  2  :  4  =  ^°°  _  =  200  lbs.  =  x. 
2x 

It  would  therefore  follow  that  an  incisal  point  angle  placed  mid- 


80 


OPERATIVE    DENTISTRY 


way  betAveen  the  gingival  wall  and  the  incisal  surface  of  the  filling 
would  be  required  to  stand  a  strain  just  double  the  force  at  the  in- 
cisal, or  place  of  impact.  In  diagram  B,  Fig.  37,  the  incisal  point 
angle  is  placed  three-fourths  of  the  way  from  the  gingival  to  the  in- 
cisal and  we  then  have : 

400 
100  lbs.  :  X  : :  3  :  4  =  — g—  —  ISSl/g  lbs.  —  x. 

This  shows  a  strain  on  the  incisal  point  angle  of  one  hundred  and 
thirty-three  pounds.    It  will  therefore  be  seen  that  the  incisal  point 


Fig.  38. — Drawing.s  to  illustrate  the  principle  of  the  lever  in  the  dislodgement  of  fillings  of  the 
fourth  class,   plans   one   and  two. 

angle  should  be  laid  as  close  to  the  incisal  edge  of  the  tooth  as  the 
strength  of  the  dentine  protecting  that  angle  will  permit  as  it  fol- 
lows that:  "Tlie  fartlier  tlie  incisal  angle  is  from  tlie  force  of  masti- 
cation the  greater  will  he  tlie  strain  on  hotJi  dentine  and  filling  at 
tJiis  angle." 

With  Fig.  38  Ave  Avill  consider  the  principles  in  a  little  more  com- 
plicated form.  Let  a  represent  the  fulcrum,  h  and  c  the  loads  and  d 
the  point  of  the  application  of  the  force.  The  radii  of  the  arcs  of 
the  circles  represent  a  fcAV  of  the  directions  from  which  force  may 
be  received  by  the  filling.    With  the  light  lines  the  force  Avould  be 


PROXIMAL    CAVITIES    IX    IXCISORS    IXVOLVIXG    AXGLE  81 

absorbed  by  the  walls  of  the  cavity.  Force  from  the  direction  of  the 
dark  lines  -wonld  pnt  into  operation  the  principles  of  the  lever. 

In  diagram  A,  Fig  38,  the  filling  would  operate  as  a  lever  of  the 
second  class  upon  the  load  at  c,  as  described  in  Fig.  37.  With  the 
gingival  point  angles  at  h  the  filling  Avould  operate  as  a  lever  of  the 
first  class  over  the  same  fulcrum  (a),  provided  the  gingival  outline 
or  fulcrum  has  been  laid  higher  than  the  point  angle  and  therefore 
nearer  the  point  of  the  application  of  the  force. 

In  case  the  gingival  margin  has  1)een  laid  lower  than  the  point 
angle  or  farther  from  the  point  of  impact  than  the  fulcrum  we  have 
a  lever  of  the  second  class  which  when  figured  out  will  draw  an  im- 
mense load  as  shown  in  the  explanation  of  Fig.  37. 

In  case  the  gingival  poiut  angles  are  cut  more  root-wise  than  the 
gingival  margin  and  we  have  a  lever  of  the  first  class  we  must  con- 
sider the  principles  of  the  l^ent  lever.  AVhen  the  direction  of  the 
force  (or  of  the  resistance)  is  not  at  right  angles  to  the  arm  or  the 
lever  on  Avhich  it  acts,  the  "le^er-arm"  is  the  length  of  the  per- 
pendicular from  the  fulcrum  to  the  line  of  the  dii'ection  of  the  force 
(or  the  resistance). 

AVe  must  therefore  conclude:  First,  that  gingival  point  angles 
should  be  placed  so  as  to  extend  more  root-wise  than  the  height  of 
the  gingival  line  at  the  proximal  (that  part  of  the  gingival  wall 
which  is  nearest  the  incisal  is  regarded  as  the  highest  point). 
Second,  the  farther  the  gingiA'al  wall  with  all  its  parts  is  from  the 
incisal  the  greater  will  ])e  the  length  of  the  power  arm  with  each 
individual  blow.  Third,  the  nearer  the  gingival  wall  is  to  the  incisal 
the  less  the  number  of  directions  from  Avhich  force  may  be  received 
which  will  act  upon  the  filling  as  a  lever. 

In  order  that  we  may  eliminate  the  principles  of  the  levers,  the 
step  cavity,  in  classes  two  and  four,  has  been  devised  as  shown  in 
diagram  B,  Fig.  38.  It  will  l>e  seen  by  the  radii  of  the  three  arcs 
drawn  that  the  increase  of  the  surface  of  the  filling  exposed  to 
force  does  not  increase  the  dangers  of  the  lever  as  the  area  of  the 
seat  of  the  filling  has  also  been  increased  Avhich  Avill  absorb  the  force 
beneath  the  increased  surface.  Again,  so  long  as  the  incisal  angle 
in  the  step  (at  c)  holds  and  the  filling  material  remains  rigid  the 
lever  principle  has  been  eliiiiinalc*!  as  regards  all  other  anchorage 
of  the  filling. 

Direction  of  the  Incisal  Angle.  I'ig.  :!!)  is  a  diawing  to  illnstrate 
the  difference  in  the  directions  Die  ])oint  anyles  take  in  tii)ping  to 
exit  with  various  filling.  Lot  the  ])('i-])('ii(licnhii-  shaft  i'e]iresent  the 
varying  length  of  (.'lass   I-'oui-  fillings  and  the  hoi-izontal  bars  the 


82 


OPERATIVE   DENTISTRY 


varying  lengths  of  the  step  hi  plan  two  of  this  class.  The  dotted 
lines  are  the  radii  of  the  various  circles  the  arcs  of  which  the  point 
angles  would  describe  in  moving  to  exit,  pivoting  on  the  gingival 
margin.  The  length  of  the  step  portion  relative  to  the  height  of 
the  filling  determines  the  direction  the  incisal  point  angle  must  take 
to  exit.  With  a  short  proximal  portion  and  a  comparatively  long 
step  portion,  the  first  movement  of  the  point  angle  is  almost  per- 
pendicular.    See  fillings  in  Fig.  39   {a,  x,  li;  also  g,  f,  n). 


Fig.  39._Drawing  to  illustrate  the  difference  in  the  directions  the  point  angle  fillings  take  in 
tipping  to  exit  with  various  fillings. 

Note  the  difference  in  the  direction  the  point  angle  would  take 
to  exit  with  an  increased  length  of  filling  inciso-gingivally.  Also 
see  li,  X,  a,  and  then  li,  x,  h,  and  on  down  until  it  is  It,  x,  g.  It  vnil 
be  seen  that  there  is  a  gradation  toward  the  horizontal  movement 
of  the  incisal  point  angle  to  exit.  Again  note  the  change  of  direc- 
tion to  exit  of  the  incisal  point  angles  in  g,  a,  i,  and  then  g,  h,  j,  then 
g,  c,  h,  and  on  down  to  g,  f,  n.  We  see  in  this  series  that  there  is  a 
gradation  toward  the  perpendicular  movement  of  the  incisal  point 


PROXIMAL    CAVITIES    IX    INCISORS   INVOLVING    ANGLE 


83 


angle  to  exit.  In  the  first  instance  "\ve  lengthened  the  axial  wall,  us- 
ing the  same  length  of  step.  In  the  second  instance  we  shortened 
the  axial  wall  and  at  the  same  time  lengthened  the  step  and  the 
change  is  more  rapid.  It  would  seem  then  that  the  direction  to  be 
given  the  incisal  point  angle  is  determined  by  the  degree  of  the 
circle  in  which  lays  a  line  drawn  from  the  deepest  portion  of  the 
incisal  point  angle  to  the  fulcrum.  (See  dotted  lines  Fig.  39.)  The 
nearer  this  line  in  a  given  case  approaches  the  perpendicular  to  the 
axial  part  of  the  filling  the  more  essential  is  it  that  the  point  angle 
be  cut  in  the  same  plane  as  the  axial  wall.  Also  the  nearer  this 
line  approaches  ninety  degrees  from  the  perpendicular  the  more  es- 
sential is  it  that  the  incisal  point  angle  be  cut  at  forty-five  degrees 
to  the  perpendicular  of  the  axial  wall. 

Bv  a  study  of  Fig.  40  it  will  be  seen  that  the  incisal  angle  of 


Fig.  40. — Drawings  to  illustrate  the  importance  which  should  be  given  to  the  proper  plac- 
ing of  the  incisal  point  angle  in  fillings  of  Class  Four,  plan  two,  with  particular  reference  to 
the  plane  in  which  wall   b — c  should  be  cut. 

A  would  be  effective  while  B  would  offer  no  resistance  to  exit  with 
a  filling  pivoting  at  a.  By  materially  shortening  the  axial  walls  of 
both,  the  point  angle  of  B  becomes  effective  and  that  of  A  ineffective. 

As  shown  in  the  drawings  in  A  the  dentine  included  in  h,  c,  d  is 
the  rotontif)n  i)roduced  by  having  dotted  line  a,  h  longer  than  line 
a,  c.  Ill  B  these  lines  are  the  same  length,  hence  no  retention.  The 
filling.'-  l)ff()iiif's  a  Ifxcr  to  lift  the  gingival  point  angles. 

The  Gingival  Angles.  h\  the  study  of  the  gingival  angle  reten- 
tion, wf  will  eliminate  the  incisal  angle  and  consider  that  it  has  been 
improperly  laid  or  has  been  Aveakened  and  llio  lexer  foreo  has  been 
transmitted  to  the  gingival  angles. 


84 


OPERATIVE    DENTISTRY 


In  Fig.  41,  a  is  the  fulcrum  and  h  the  extreme  point  of  the  angle. 
Dotted  lines  a-h  are  the  radii  of  the  circles  the  arcs  of  which  the 
point  angle  fillings  would  describe  in  going  to  exit.  The  two 
gingival  point  angles  should  be  of  different  depths  so  that  they  Avill 
describe  the  arcs  of  different  circles  in  being  drawn  to  exit.  It  is 
most  cojivenient  to  make  the  gingivo-axio-lingual  the  deeper. 


A  B 

Fig.  41. — A  study  in  the  proper  placing  and  deptli  of  the  gingival  angles. 


.../ 


Fig.   42. — A  study  of  the  planes  in  which  the  gingival  angles  should  be  laid. 

It  is  also  essential  that  the  two  gingival  point  angles  be  so  laid 
that  the  circles,  the  arcs  of  which  the  point  angle  fillings  describe  in 
passing  to  exit,  stand  in  different  planes  as  illustrated  in  Fig.  42. 
Failure  to  observe  the  last  two  principles  given  removes  retention 
form  as  regards  the  gingival  angles. 


PROXIMAL    CAVITIES    IX    INCISORS   INVOLVING    ANGLE 


85 


First  Plan  of  Angle  Restoration.    (Class  Four.) 

The  first  plan  of  anchorage  is  made  by  undercutting  the  incisal 
edge.  This  plan  is  indicated  in  teeth  of  rather  thick  incisal  edge 
that  are  rather  short  and  stocky  as  they  have  a  greater  body  of  den- 
line  near  the  angles  upon  Avhich  to  depend. 


Fig.   43. — Cavity  of  Class  Four,  plan  one,  for  cohesive  gold. 


Fig.    44. — Class   Four,   plan   one,   cavity    filled.      Labial    and    lingual   views. 
Cavity  shown  in  Fig.  43. 

As  a  rule  the  horns  of  tlic  i)ulp  in  siicli  teeth  arc  Avell  retracted,  at 
lejist  in  adult  mouths,  and  there  is  less  danger  of  pulp  exposure  as 
compared  Avith  the  teeth  of  thin  edges  and  angular  outline.  If  this 
plan  has  been  decided  upon,  Iho  cavily  sh(mld  be  cut  well  to  the 


86 


OPERATIVE   DENTISTRY 


gingival,  particularly  at  the  gingival  angles,  in  some  cases  to  the  ex- 
tent that  the  gingival  wall  is  made  convex  to  the  incisal. 

The  Gingival  Point  Angles  should  be  deep  and  well  defined  at 
the  expense  of  both  gingival  and  axial  walls.  This  is  particularly 
true  of  the  gingivo-lingual  angles,  to  protect  against  the  torsion 
strain. 

To  Assist  the  Incisal  Angle.  To  resist  the  tipping  strain  both  the 
labial  and  lingual  Avails  should  be  slightly  grooved  along  the  axio- 
labial  and  axio-lingual  line  angles  much  in  the  same  way  as  with 
large  Class  Three  cavities. 

The  Labial  Outline  should  so  proceed  that  the  completed  filling 
will  be  of  about  equal  width  for  its  entire  length  except  that  as  it 
approaches  the  incisal  edge  it  should  be  slightly  curved  to  the  axial. 


Fig.  45. — Shows  incisal  outline  in  Class  Four,  plan  one,  fillings  with  direct  occlusion. 

A  Rule  for  Labial  Outlines.  All  cavity  outlines  in  incisal  angle 
restorations  should  curve  to  the  axial  as  they  approach  the  incisal 
edge.  The  nearer  this  outline  approaches  the  central  axial  line  of 
the  tooth  the  greater  should  be  the  curve.  When  the  central  axial 
line  is  reached  by  a  cavity  outline,  the  same  should  then  be  extended 
to  involve  the  opposite  angle.  There  are  exceptions  to  the  above 
rule  but  maximum  resistance  to  stress  is  only  thereby  obtained. 

The  Necessity  for  Curving  to  the  Axial.  When  approaching  the 
incisal  edge  curve  to  the  axial  that  the  last  rods  at  the  cavo-surface 
angle  may  be  adequately  supported.  A  large  per  cent  of  fillings 
where  this  precaution  has  been  neglected  fail,  showing  a  primary 
fault  due  to  the  breaking  away  of  the  enamel  at  this  point. 


PROXIMAL    CAVITIES   IN    INCISORS   INVOLVING   ANGLE  87 

The  Incisal  Outline  as  it  crosses  the  incisal  edge  of  thick  teeth 
shoukl  have  in  its  center  a  curve  toward  the  axial  caused  by  a  slight 
groove  in  the  center  of  the  dentine.  This  groove  which  ends  at  this 
point  in  the  cavity  outline  should  originate  at  the  external  end  of 
the  incisal  line  angle.  If  there  is  sufficient  dentine,  and  there  gen- 
erally will  be  in  the  class  of  cases  calling  for  this  plan  of  restora- 
tion, this  groove  is  of  best  service  if  it  be  a  flattened  groove  and 
made  Avith  a  small  hoe  or  hatchet.     (Fig.  45.) 

The  LingTial  Outline  should  be  the  same  as  for  large  Class  Three 
except  in  the  incisal  third  Avhen  it  should  curve  to  the  axial  even 
more  rapidly  than  the  labial  outline  and  for  a  longer  distance,  re- 
sulting in  cutting  away  more  enamel  from  the  lingual  than  is  re- 
moved by  the  labial  outline.  This  is  made  necessary  from  the  fact 
that  all  stress  is  from  the  lingual. 

With  Lower  Incisors  the  reverse  is  true  and  it  is  necessary  to  re- 
move slightly  more  of  the  labial  enamel  in  angle  restoration,  a  fact 
Avhicli  materially  mars  these  teeth  from  an  esthetic  point  of  view. 
Fortunately  Ave  have  comj^aratiA-ely  fcAv  angles  to  restore  on  loAver 
incisors,  but  Avhen  they  are  presented  the  fact  must  be  borne  in 
mind  that  they  receive  the  major  portion  of  stress  from  the  inciso- 
labial  direction. 

Second  Plan  of  Angle  Restoration.     (Class  Four.) 

The  second  plan  of  restoration  is  indicated  in  teeth  that  are  of 
medium  thickness,  particularly  if  they  are  of  angular  build  or  have 
a  direct  contact  on  the  incisal  edge  either  in  occlusion  or  articula- 
tion, and  consists  in  the  additon  to  plan  one  of  Avhat  is  termed  the 
incisal  step.  The  cavity  proper  is  prepared  the  same  as  has  been 
outlined  in  plan  one  up  to  the  forming  of  the  step. 

The  Incisal  Edge  is  cut  aAvay  Avith  a  narroAv-edged  carborundum 
stone,  the  cutting  being  extended  toAvard  the  opposite  angle  a  dis- 
tance equal  to  the  Avidth  of  the  cavity  proper.  The  incisal  outline 
should  avoid  both  the  centers  of  primary  calcification  and  the  point 
of  coalescence,  two  Aveak  places  in  enamel  construction.  The  cut- 
ting should  be  more  at  the  expense  of  the  lingual  side  of  the  tooth 
by  onc-h;i]f  to  one  millimeter. 

The  Depth  of  This  Step,  inciso-gingivally,  Avill  depend  upon  the 
thickness  of  the  cutting  edge,  and  the  probable  stress  it  Avill  receive. 
The  thinner  the  edge  and  the  greater  the  probable  stress,  the  deep- 
er must  be  the  step.  The  majority  of  cases  Avill  shoAV  not  to  exceed 
one  milliiiieter  of  gold  on  the  labial  in  the  step  portion. 

Technic  of  Cutting.     A  small   i-onnd  bur  is  then  used  to  cut  a 


88 


OPERATIVE   DENTISTRY 


groove  in  this  newly  formed  pulpal  wall,  near  the  clento-enamel 
junction  next  to  the  lingual  plate  of  enamel.  The  lingual  enamel  is 
then  removed  with  a  chisel  thus  carrying  that  portion  of  the  pulpal 
wall  to  a  loAver  level.    This  process  is  continued  until  it  is  at  least 


Fig.  46. — Cavity  of  Class  Four,  plan  two,  for  cohesive  gold. 


Fig.  47. — Class  Four,  plan  two,  filled.     Labial  and  lingual  views.     A  very  popular  method. 
Cavity  shown  in  Fig.   46. 

one-half  millimeter  to  one  millimeter  lower  than  the  labial  portion 
of  the  pulpal  wall.  This  leaves  the  major  portion  of  the  dentine  sup- 
porting the  labial  plate  of  enamel. 

The  Point  Angle  in  the  Step  Portion  should  be  deepened  and  made 


PROXIMAL    CAVITIES   IN    INCISORS   INVOLVING    ANGLE 


89 


acute  largely  at  the  expense  of  the  piilpal  Avail.  This  will  place  it  in 
just  the  right  position  to  resist  stress  from  the  probable  source  and 
prevent  tipping.     (See  Fig.  37.) 

This  Second  Plan  is  Particularly  Indicated  in  eases  of  mueli  wear 


Fig.    48. — Cavity   of   Class   Four,   plan   tliree.   for   cohesive   gold. 


A  B 

Fig.   49.— Class   Four,   plan   three,   filled.      Laliial  and   lingual   views.     Cavity  shown   in   Fig.    48. 

on  the  incisal,  due  to  wliat  is  called  "end-to-end"  bite.  However, 
in  such  cases  all  of  the  exposed  dentine  on  the  incisal  edge  should 
be  included  in  the  .step  and  it  is  not  necessary  to  remove  much  of 
either  of  the  lalnal  ov  liiiuua!  ])lMtes  of  enamel.     In  such  cases  the 


90  OPERATIVE   DENTISTRY 

step  portion  should  be  retentive  throughout  as  it  is  liable  to  be 
worn  away  by  subsequent  wear,  growing  thinner  from  year  to  year, 
hence  the  necessity  of  retentive  form  from  cavo-surface  angle  to  the 
base  line  angles. 

Third  Plan  of  Angle  Restoration.     (Class  Four.) 

This  plan  is  the  addition  to  plan  one  of  the  lingual  step.  It  is 
particularly  indicated  in  cases  of  long  incisors  which  are  quite  thin 
labio-lingually  and  subjected  to  a  long  sweep  of  the  lower  incisors 
in  the  movements  of  articulation,  or  what  is  spoken  of  as  the  ''scis- 
sors bite." 

Also  Indicated  in  cases  where  the  axial  wall  extends  out  to  the 
enamel  edge  on  the  lingual  thus  removing  the  lingual  wall. 

The  Labial  Outline  is  the  same  as  with  the  first  plan  of  restora- 
tion. The  step  is  formed  on  the  lingual  b;^  cutting  away  the  enamel 
from  the  lingual  surface  of  the  tooth  toward  the  central  axial  line 
for  a  distance  of  from  one  to  two  millimeters  at  the  incisal  edge. 

As  the  gingival  is  approached  the  cutting  is  narrowed  to  a  point 
where  the  marginal  ridge  may  be  crossed  at  right  angles  to  meet 
the  gingival  portion  of  the  outline.  This  will  form  a  V-shaped  axial 
Avail  of  dentine  facing  the  lingual.  There  should  be  cut  a  flat- 
floored  groove  in  this  dentine  parallel  with  the  remaining  enamel 
Avail  ending  in  the  gingiA^o-axio -lingual  angle  AA^hich  should  be  an 
acute  conA'enience  angle.  The  plan  giA^es  great  resistance  to  stress 
from  lingual  pressure. 

Fourth  Plan  of  Angle  Restoration.     (Class  Four.) 

This  plan  consists  of  resorting  to  all  of  the  features  of  resistance 
and  retention  embodied  in  plans  tAVo  and  three  by  combining  both 
the  lingual  and  incisal  steps.  Each  of  these  has  been  fully  de- 
scribed and  the  method  of  cutting  both  steps  to  the  same  should  not 
prove  hard  to  accomplish. 

By  this  plan  the  maximum  resistance  and  retention  forms  are  se- 
cured Avith  the  minimum  loss  of  dentine.  It  must  be  remembered 
that  resistance  to  stress  is  good  in  proportion  to  the  amount  of  se- 
curing dentine  retained,  hence  it  should  be  sparingly  cut  away. 
The  remoA'al  of  enamel  to  lay  bare  dentine  Avherein  to  lay  anchor- 
age is  only  harmful  from  the  esthetic  standpoint  and  is  of  little  loss 
when  taken  aAvay  from  a  surface  not  in  vicAV,  as  is  the  case  Avhen  Ave 
cut  aAvay  a  portion  of  the  lingual  plate. 

Cavities  in  the  Distal  of  Superior  Cuspids.  On  account  of  the 
peculiar  articulation  of  the  lingual  surface  of  superior  cuspids  this 


PROXIMAL    CAVITIES   IN   INCISORS   INVOLVING   ANGLE 


91 


cavity  has  been  left  for  separate  consideration.  The  plan  given  is 
a  modification  of  plan  three,  using  a  lingual  step  not  unlike  the  oc- 
clusal step  in  a  class  two  cavity. 


Fig.   50. — Cavity  of  Class  Four,   plan   four,   for  cohesive  gold  showing  maximum   anchorage 
with  a  minimum  loss  of  dentine.      The  use   of  this  plan  is  advised  when  the   lingual  stress   is 


great. 


A  B 

Fig.    51. — Class   Four,   jilan   four,   filled.      I.aliial    and   lingual   views.      Cavity  shown   in  Fig.    50. 

Access  is  an  easy  uiattei-  as  the  decay  is  in  the  most  prominent 
part  of  the  distal  surface  and  ;i  little  work  with  the  chisel  gives  ac- 
cess to  the  cavitv. 


92 


OPERATIVE   DENTISTRY 


Outline  Form.  In  outlining  the  cavity  proper  most  of  that  vv^hich 
has  been  said  about  plan  one  should  be  followed  here. 

As  to  the  lingual  outline  and  that  of  the  step  particular  attention 
must  be  paid  to  so  placing  the  margins  as  to  remove  them  as  much 
as  possible  from  the  stress  of  articulation. 

The  Step.  The  lingual  step  is  added  to  this  cavity  as  it  ma- 
terially assists  in  retention,  resistance  and  convenience  forms. 

In  the  laying  of  the  walls  of  the  step  portion  the  particulars 
are  carried  out  much  as  though  the  lingual  surface  of  the  cuspid 
were  an  occlusal  surface,  as  next  to  an  occlusal  surface  it  receives 
the  greatest  stress  in  articulation. 

Axial  Walls.    It  will  be  seen  that  this  cavity  has  two  axial  walls. 


Fig.   52. 


Fig.    5; 


Fig.  52. — Cavity  of  Class  Four,  modified  plan  three,  for  cohesive  gold  in  the  distal  of 
the  superior  cuspid.  This  plan  is  sometimes  tised  to  advantage  in  the  incisors  when  the 
tooth  is  short  and  stocky.     In  such  cases  the  lingual   step  is  made  to  include  the  lingual  pit. 

Fig.   53. — Class  Four,  modified  plan  three,  filled.     Cavity  shown  in  Fig.   52. 

The  one  in  cavity  proper  is  the  axial,  while  that  in  the  step  is 
termed  the  lingual  axial  wall. 

The  Lingnal  Axial  Wall  should  be  placed  on  a  plane  parallel  with 
the  lingual  surface  of  the  tooth.  Its  surrounding  line  angles  should 
be  laid  just  below  the  dento-enamel  junction. 

Convenience  Form  in  this  cavity  is  pretty  well  secured  by  the  ad- 
dition of  this  lingual  step,  as  the  filling  is  then  easily  built  in  from 
the  lingual  direction.  Both  gingival  point  angles  in  the  cavity 
proper  should  be  made  convenience  angles  as  well  as  the  axio- 
gingivo-mesial  point  angle  in  the  step  portion. 


CHAPTER  XVI. 

MANAGEMENT  OF  CAVITIES  IX  THE  GINGIVAL  THIKD. 
(CLASS  FIVE.) 

Gingival  Third  Cavities  Differ  from  all  other  cavities  in  the  teeth 
ill  that  they  uri<iinate  on  perfectly  smooth  surfaces  generally  Avith- 
out  flaAv  in  enamel  formation  and  without  covering  of  any  kind,  or 
to  state  it  more  concisely,  there  seems  to  be  no  predisposing  cause. 

Their  Prevention  is  an  easy  matter,  as  the  accumulation  of  sordes 
which  is  the  sole  exciting  cause,  is  unprotected  and  of  easy  access  to 
the  brush  so  that  patients  with  this  clnss  of  decay  are  paying  the 


A  B 

Fig.    54. — Cavities  Class   Five  for  cohesive  gold   or  amalgam. 

penalty  for  the  careless  neglect  of  the  siiii])l('st  foi-nis  of  oral  cleanli- 
ness. "With  these  facts  befoi-e  us  it  becomes  tlie  duty  of  every  practi- 
tioner to  fully  advise  the  patients  of  the  neglect  of  their  mouths  in 
this  pai'ticular  locality,  in  an  effort  to  check  fartlier  destruction. 

The  Tendency  to  Spread  in  the  Enamel  is  a  cliai-acleiistic  of  this 
class  of  cavities.  They  usually  originate  near  the  center  of  the 
buccal  sui-face  near  the  fi-ec  mar-gin  of  the  gum  and  seldom  stop- 
until  they  liave  extended  both  mcsially  <ind  dist;ill\-  neai'ly  to  the 
angles.  The  fact  that  the  eno-oachment  seldom  reaches  the  angle 
in  tho  extei-nal  einimcl   decay,  is  a  point  to  be  considered  in  the 

93 


94 


OPERATIVE   DENTISTRY 


study  of  extension  for  prevention  in  this  class  of  cavities.  It  ap- 
pears that  when  the  outline  is  carried  quite  to  the  angle  that 
secondary  caries  rarely  occurs. 

The  Gingival  Outline  should  be  laid  below  the  gum  line  for  its 
entire  length  until  the  angles  are  reached  when  it  should  emerge 
from  beneath  the  gum  at  a  right  angle  to  the  free  margin  of  the 
gum. 

The  Occlusal  or  Incisal  Outline  should  be  carried  to  a  region 
of  sound  enamel.  Where  this  extension  does  not  carry  this  outline 
farther  than  one  millimeter  from  the  free  margin  of  the  gum  farth- 
er extension  should  be  made.  With  teeth  surrounded  by  a  heavy 
gum,  particularly  if  there  seems  to  be  a  condition  of  hypertrophy 


A  B 

Fig.   SS. — Class  Five   filled.     Cavities  shown  in  Fig.   54. 

present,  the  occlusal  outline  should  be  laid  at  least  two  millimeters 
from  the  border  of  the  gum. 

Retention  Form.  Retention  is  secured  by  squaring  out  the  four 
point  angles.  The  axial  wall  should  generally  be  left  as  decay  has 
left  it  in  the  central  portion.  Any  subsequent  cutting  should  be 
of  such  a  nature  as  would  tend  to  make  it  convex  to  the  external, 
or  so  to  speak,  the  miniature  of  the  tooth's  surface  in  which  it  is 
being  cut.  An  effort  to  cut  a  flat  axial  wall  mesio-distally  will 
often  endanger  the  pulp  and  is  unnecessary  as  these  cavities  need 
no  resistance  form. 

In  Large  Buccal  Decay  often  the  gum  has  so  grown  into   and 


CAVITIES   IN    THE    GINGIVAL    THIRD  95 

filled  the  cavity  that  the  adjustment  of  the  clamp  and  rubber  dam 
is  difficult  or  impossible.  In  such  cases  if  the  pulp  is  not  involved 
much  assistance  is  secured  by  packing  the  cavity  full  of  gutta- 
percha base  plate  allowing  it  to  crowd  well  down  upon  the  gum. 
In  a  few  days  the  gum  will  have  receded  or  have  been  absorbed 
sufficiently  to  permit  convenient  access. 

If  the  Pulp  is  Involved  and  requires  extirpation  make  the  appli- 
cation of  the  devitalizing  agent,  covering  this  with  amalgam  which 
should  fill  the  cavity.  Care  should  be  taken  that  the  gingival  wall 
has  been  planed  to  a  solid  condition.  During  this  operation  dry- 
ness may  be  obtained  by  the  assistance  of  cotton  rolls. 

When  case  returns  the  clamp  will  ride  on  the  amalgam  at  the 
gingival  and  access  to  the  pulp  may  be  had  through  the  upper 
portion  of  the  amalgam.  After  the  pulp  canals  have  been  filled 
the  dam  may  be  removed,  the  remainder  of  the  amalgam  excavated 
and  cavit}'  preparations  proceeded  with,  as  well  as  the  placing  of 
an  amalgam  filling,  under  dry  conditions  by  the  use  of  cotton  rolls. 

If  Gold  is  to  Be  Used  the  gold  inlay  is  clearly  indicated  as  pro- 
ducing the  best  results  with  the  least  tax  upon  patient  and  oper- 
ator. 

With  Labial  Cavities  in  the  gingival  third  the  Hatch  clamp  will 
expose  nearly  every  case  presented  and  render  access  not  difficult 
for  the  introduction  of  a  cohesive  gold  filling.  In  cases  of  ex- 
tensive gum  recession  on  labial  exposures  the  porcelain  inlay  is 
clearly  indicated  and  is  considered  in  the  chapters  on  that  subject. 


CHAPTER  XVII. 

MANAGEMENT  OF  ABRADED  SURFACES.     OCCLUSAL  AND 
INCISAL.     (CLASS  SIX.) 

Definition.  Class  six  includes  the  group  of  cavities  necessary 
for  the  repair  of  injuries  to  the  teeth  through  the  loss  of  a  portion 
of  their  articulating  surfaces  as  the  result  of  wear.  The  condition 
is  abnormal  and  the  extent  of  the  destruction  of  tooth  substance 
is  by  no  means  in  proportion  to  the  amount  of  use  to  which  the 
teeth  have  been  subjected.  However  it  will  be  noticed  in  mouths 
with  teeth  of  short  cusps,  and  particularly  if  the  incisors  occlude 
directly  upon  the  incisal  edge,  that  there  is  an  abnormal  amount  of 
lateral  motion  in  the  act  of  articulation,  and  in  such  mouths  we 
find  the  maximum  loss  of  tx)oth  substance  at  any  given  age. 

Cause  Not  Wholly  Clear.  Yet,  that  friction  is  the  sole  cause  for 
this  lesion,  can  not  be  demonstrated,  as  the  surfaces  thus  affected 
do  not  show  the  exact  impression  of  the  opposing  teeth,  neither  is 
this  condition  always  delayed  till  advanced  years.  Cases  will  be 
occasionally  met  with  in  the  mouths  of  people  in  middle  life  show- 
ing the  advanced  stages  of  this  trouble. 

At  the  same  time  locations  will  be  found  on  the  occlusal  surfaces 
of  teeth  AA'hich  at  one  time  must  have  been  in  articulation  but  are 
so  far  lost  and  seemingly  worn  away  that  they  could  not  be 
brought  into  occlusion. 

It  would  seem  from  a  study  of  a  great  number  of  cases  that 
there  must  be  some  causes  predisposing  and  exciting  not  yet  un- 
derstood. It  is  not  improbable  that  the  cause  is  a  fault  in  tooth 
structure,  not  so  much  in  the  constituents  of  the  tooth  as  in  the 
lack  of  strength  in  their  coml^ination.  This  conclusion  would  seem 
plausible  from  the  fact  that  teeth  similarly  situated  and  of  the 
same  chemical  analysis  are  affected  to  a  different  degree  by  even 
slight  friction.    The  bond  of  union  does  not  seem  to  be  so  strong. 

The  Object  in  Filling  or  in  making  a  cavity  to  fill  is  to  perma- 
nently check  the  loss  of  tooth  substance  by  entirely  covering  the 
affected  surface  with  a  substance  that  will  resist  the  full  force  of 
mastication. 

Occlusal  Surfaces.  In  occlusal  surfaces;  particularly  molars 
showing  the  first  stages  of  general  erosion,  early  interference  is  ad- 
vised.    As  soon  as  a  cusp  is  lost  it  should  be  restored  and  if  pos- 

96 


ABRADED  SURFACES.   OCCLUSAL  AND  IXCISAL  97 

sible  Iniilt  high  -with  gold,  preferably  an  alloy  of  gold,  either 
platinized  foil  or  a  east  inlay  of  gold  alloy. 

This  Early  Restoration  of  cusps  to  their  full  height  will  tend  to 
restrict  the  lateral  motion  of  the  mandible  in  mastication,  which 
seems  to  be  a  factor  in  this  dissolution. 

Cavity  Preparation.  These  cavities  should  be  prepared  as  class 
one  and  shoukl  be  retentive  throughout. 

If  the  Major  Portion  of  the  Occlusal  Surface  of  a  single  molar  is 
affected  the  whole  occlusal  surface  should  be  loAvered  about  one  milli- 
meter and  the  same  restoi'ed  with  a  cast  inlay,  sometimes  termed 
an  onlay.  This  is  advised  from  the  fact  that  the  occlusal  side  of 
the  filling  may  better  fit  the  surface  of  the  occluding  teeth.  This 
jnay  and  probal)ly  will  necessitate  the  devitalization  of  this  in- 
dividual tooth  Avhen  the  pulp  chamber  should  be  utilized  for  an- 
chorage. 

If  Contact  Points  have  been  reached  by  this  cutting,  a  mesio-oc- 
clusio-distal  cavity  is  imperative. 

When  Wear  is  General  opening  the  bite  to  the  extent  of  about 
one  millimeter  is  preferable  to  cutting  away  any  more  tooth  sub- 
stance than  is  necessary  for  firm  foundation  and  a  correct  outline. 

With  Incisal  Abrasion,  if  the  wear  is  not  excessive,  the  building 
on  of  the  "shoe,"  or  covering  the  entire  incisal  end  of  the  tooth 
with  platinized  gold  is  the  best  practice.  The  gold  inlay,  which  is 
treated  in  the  chapters  on  inlays,  is  also  of  service. 

When  there  is  excessive  incisal  Avear  opening  the  bite  to  practi- 
cally no]-mal  is  indicated,  using  gold  for  the  posterior  teeth  and 
the  poi'celain  crown  for  the  anterior. 

The  Entire  Enamel  Edge  on  the  occlusal  and  incisal  surfaces 
must  \)e  covered  with  a  protecting  layer  of  metal  as  with  these 
teeth  the  bond  of  union  seems  to  be  very  Aveak,  particularly  at 
the  dento-enamel  junction,  and  they  will  cliip  away  if  not  wholly 
protected  from  the  foi-ce  of  mastication. 


CHAPTER  XVIII. 
CAVITY  PKEPARATION  FOR  GOLD  INLAYS. 

Definition.  An  inlay  is  a  body  placed  within  a  previously  pre- 
pared excavation.  As  applied  to  the  filling  of  teeth  it  refers  to  the 
process  whereby  the  filling  is  inserted  into  the  cavity  of  a  tooth  in 
one  piece  and  retained  there,  by  the  assistance  of  cement. 

The  Materials  in  most  common  nse  are  porcelain,  pure  gold,  al- 
loys of  gold,  as  well  as  alloys  of  base  metals. 

The  Indications  for  a  Gold  Inlay.  First.  In  large  contour 
restorations,  as  there  is  a  material  saving  of  both  time  and  energy 
on  the  part  of  both  patient  and  operator.  Such  cases,  particular- 
ly with  posterior  teeth  are  frequently  crowned  with  the  shell  gold 
ero"\vn  with  its  almost  universally  irritating  band,  when  the  inlay 
could  be  of  greater  service. 

Second.  "When  it  is  difficult  to  maintain  dry  conditions  for  a 
long  period  of  time  about  a  cavity,  as  with  large  gingival  cavities 
in  molars  and  bicuspids. 

TJiird.  When  there  are  extensive  occluding  surfaces  to  be  re- 
stored. It  is  much  easier  to  cast  a  correct  contour  than  to  build 
up  with  the  plugger  point  which  is  largely  guesswork  when  the 
rubber  dam  is  in  position. 

Fourtli.  When  it  is  desired  to  put  in  a  number  of  fillings  in  a. 
given  short  time.  In  such  cases  the  operator  can  make  the  wax 
models,  and  engage  the  help  of  the  laboratory  in  completing  the 
fillings  while  he  is  still  busy  with  other  fillings  at  the  chair. 

Fiftli.  When  the  necessary  force  to  properly  condense  a  cohe- 
sive gold  filling  is  not  permissible,  as  with  loosened  teeth,  or  in- 
valid patients. 

Gold  Inlays  Are  Not  Indicated  in  small  cavities,  or  shallow  cav- 
ities, unless  the  outline  is  extensive. 

The  Cavity  Preparation  for  a  gold  inlay  does  not  materially  dif- 
fer from  that  which  has  already  been  advised  in  the  preceding 
chapters.  It  is  possible  to  construct  an  inlay  without  change  for 
nearly  every  cavity  which  has  been  correctly  prepared  to  receive 
a  cohesive  gold  filling.  However  if  the  order  of  precedure  is  slight- 
ly rearranged  the  operation  is  simplified. 

This  Change  in  the  Order  would  be  to  put  retention  form  last,  at- 
tending to  that  part  of  the  cavity  preparation  after  the  model 
has  been  made  and  just  before  setting  the  inlay. 

98 


CAVITY    PREPARATION   FOR   GOLD   INLAYS  99 

In  cases  where  this  has  not  been  done,  or  the  cavity  is  naturally 
retentive,  the  retention  should  be  temporarily  covered,  as  will  later 
be  described,  while  making  the  model. 

Change  of  Position  of  Retention  Angles.  It  is  quite  ideal  to  cut 
just  as  heavy  retention  angles  in  the  different  classes  of  cavities 
for  gold  inlays,  as  for  cohesive  gold,  only  they  should  be  laid  in  a 
diiferent  position  and  cut  at  the  expense  of  the  base  walls  rather 
than  the  surrounding  walls,  in  order  to  give  the  cavity  draw. 
This  feature  of  the  cavity  preparation  will  be  described  as  we  con- 
sider the  preparation  of  cavities  by  classes  farther  on  in  this 
chapter. 

The  Order  of  Procedure  for  Inlays  Avould  then  be  as  follows : 

1.  Gain  access. 

2.  Outline  form. 

3.  Resistance  form. 

4.  Convenience  form. 

5.  Removal  of  remaining  decay. 

6.  Finishing  enamel  walls. 

7.  Toilet  of  the  cavity. 

8.  Retention  form,  which  is  given  as  the  fourth  order  in  other 
forms  of  fillings. 

Gaining'  Access  for  inlay  filling  is  the  same  as  that  with  other 
fillings  as  far  as  surgical  procedure  is  concerned.  No  more  tooth 
substance  should  be  cut  awaj^  on  this  account. 

When  using  preliminary  separation  for  access,  there  should  be 
in  most  of  Classes  Two  or  Three  cavities,  more  room  secured,  as 
this  will  materially  assist  in  getting  a  coi-rect  wax  pattern  as  well 
as  aid  in  the  process  of  placing  the  inlay. 

Resistance  Form  for  Inlays  should  receive  the  same  careful  con- 
sideration as  gixoii  foi-  otlier  fillings.  Weakened  enamel  walls 
should  be  protected  not  only  from  the  su])se(iuent  force  received 
in  stress  but  from  the  stress  of  setting  the  inlay.  Flat  seats  for  all 
inlays  are  imperative.  The  usual  steps  in  Classes  Two  and  Four 
are  called  for  as  an  impoi-taiit  factor  in  retention  to  resist  the  tip- 
pin  ir  strain. 

Convenience  Form  for  Inlays  shonld  not  be  pi-acticed  to  excess. 
No  convenience  points  arc  reqiiiiod.  'V\\v  inajor  poi-tion  of  con- 
venience form  should  be  gaiiu'cl  tlir()n<_;li  s('i)a ration,  preferably 
slow  separation. 

Removal  of  Remaining  Decay.  Wlicii  it  has  been  fully  deter- 
mined thai  Il)(!  ])ulp  is  not  to  he  removed,  some  decay  may  be  left  on 
the  axial   wall,  or  in  the  region  of  the  bucco-axial  or  the  linguo- 


100  OPERATIVE    DENTISTRY 

axial  line  angles,  until  the  inlay  lias  been  cast  and  fitted.  It 
should  then  be  removed  and  the  dentine  over-lying  the  pulp,  if 
hypersensitive  to  thermal  changes,  given  a  coat  of  cavity  varnish. 
Allowing  this  softened  dentine  to  remain  during  the  interim  be- 
tween the  making  of  the  pattern  and  the  setting  of  the  inlay,  will 
protect  the  pulp  against  irritation  and  save  devitalization  before 
setting  the  inlay. 

The  Finishing  of  the  Enamel  Walls  will  necessarily  come  in  at 
this  point  as  all  cutting  of  the  external  outline  of  the  cavity  must 
be  completed  before  proceeding  to  make  the  pattern.  The  only 
change  advisable  is  that  the  cavo-surface  angle  should  be  more  ob- 
tuse, and  the  bevel  angle  should  not  be  as  deeply  buried,  which 
results  in  a  thinner  metal  edge. 

This  will  assist  in  burnishing  the  margins  to  a  closer  adaptation 
in  the  final  finish. 

More  Beveling  at  the  Cavo-surface  Angle  should  be  resorted  to 
for  two  reasons.  First,  the  gold  inlay  should  have  a  margin  of 
rather  an  acute  angle  in  order  that  the  material  may  be  burnished 
more  closely  to  the  margin.  Second,  during  the  process  of  setting 
the  inlay  and  burnishing  the  margins,  the  cavo-surface  angle  stands 
in  great  danger  of  being  fractured. 

The  Toilet  of  the  Cavity  for  Gold  Inlays.  Herein  lies  the  great- 
est weakness  in  inlay  methods.  No  cavity  margin  is  surgically 
clean  after  it  has  been  moistened  or  been  in  contact  with  the  inlay 
wax  pattern. 

After  the  pattern  has  been  formed  and  removed  our  methods 
will  not  permit  of  again  planing  the  cavity  surfaces  and  particu- 
larly the  margins,  which  is  the  only  way  to  render  them  entirely 
clean. 

Hence  we  are  forced  to  wash  the  cavity  walls  just  before  setting 
the  inlay  with  solvents  of  the  substances  which  have  contaminated 
them.  "Without  going  into  detail,  it  is  advised  that  the  cavity  be 
thoroughly  scrubbed  with  chloroform,  then  absolute  alcohol  as  a 
second  cavity  toilet,  and  immediately  the  cavity  be  flowed  with  the 
cement,  introducing  the  inlay  under  dry  conditions. 

Line  of  Approach.  In  inlay  work  the  cavities  should  be  ap- 
proached from  the  direction  in  which  they  are  to  receive  stress 
during  service. 

In  withdrawing  the  wax  pattern  and  when  the  inlay  is  placed, 
each  should  travel  parallel  with  a  line  drawn  from  the  seat  of  the 
cavity  to  the  source  of  the  force  of  mastication.  This  line  of  ap- 
proach is  good  practice  with  any  filling,  but  is  more  essential  with 


CAVITY  PREPARATION  FOR  GOLD  INLAYS 


101 


the  gold  inlay  than  the  cohesive  gold  filling,  for  we  do  not  have  the 
assistance  of  the  elasticity  of  the  dentine  in  retention  made  pos- 
sible by  the  use  of  the  wedging  principle  in  the  manipulation  of 
cohesive  gold. 

Preparation  of  Cavities  of  Class  One. 

Of  the  cavities  of  this  class  calling  for  gold  inlays  only  the  large 
occlusal  surface  cavities  in  molars  are  of  importance.  Small  pit 
and  fissure  cavities  are  more  quickly  and  easily  filled  by  other 
methods. 

Outline  Form.     In  large  occlusal  cavities  the  outline  should  be 


A  B 

Fig.  56. — Cavities  of  Class  One  for  gold  inlays.     Cavity  side  of  inlays  shown. 

SO  carried  as  to  avoid  eiiiiiiences  at  the  crest  of  mai'i>inal  I'idge. 
When  this  is  reached  on  the  buccal  or  lingual  the  outline  should 
include  the  marginal  ridge  and  at  least  one  millimeter  of  the  axial 
Avail  be  involved.  All  deep  grooves  should  be  included.  The 
curves  should  be  as  generous  as  possible. 

Resistance  Form.  The  same  rules  apply  as  to  other  fillings. 
W'lieii  iiiucii  of  the  supporting  dentine  has  been  removed  through 
decay  or  cavity  preparation  from  either  the  buccal  or  lingual  walls, 
that  portion  Avithiii  the  cavity  should  be  covei-ed  with  a  thin  layer 
of  black  wax.  which  prevents  the  wax  pattern  fi-om  coming  in  con- 


102 


OPERATIVE   DENTISTRY 


tact  with  these  walls.  The  cast  mlay  will  then  not  touch  these 
walls  during  the  process  of  introduction,  which  will  often  save  a 
fracture  of  these  walls,  due  to  stress  from  within  when  driving  the 
inlay  home  to  a  seat. 

The  Major  Portion  of  Retention  Form  comes  in  for  considera- 
tion after  the  inlay  has  been  cast  and  fitted  and  just  before  ce- 
menting to  place.    However,  a  flat  seat  and  nearly  parallel  walls 


Fig.  57. — Class  One  inlay  in  position  showing  gold  wire  cast  in  the  filling,  which  was  put 
into  the  wax  pattern  to  support  the  long  buccal  arin.     Cavity  shown  at   (S)    Fig.   56. 

to  this  seat  with  fairly  definite  angles,  is  necessary  to  guard  against 
the  tipping  strain  and  produce  proper  retention  form. 

Preparation  of  Cavities  of  Class  Two. 

Large  proximal  cavities  in  molars  and  biscupids  are  successfully 
handled  with  this  method  of  filling. 

Access.  Preliminary  separation  is  of  the  greatest  service  here 
and  should  be  general  practice  as  much  cutting  for  convenience 
form  is  avoided,  and  better  contact  secured. 

Complete  Preliminary  Separation  very  materially  facilitates  the 
removal  of  the  wax  pattern  as  the  operator  does  not  have  to  be 
as  careful  about  having  his  wax  pattern  tight  against  the  surface 
of  the  adjacent  tooth.  In  addition  to  the  preliminary  separation 
before  making  the  pattern,  it  is  to  the  advantage  of  the  operator 


CAVITY  PREPARATION  FOR  GOLD  INLAYS 


103 


to  pack  the  case  for  additional  separation  during  the  interim  be- 
tween making  the  pattern  and  setting  the  inlay. 

Outline  Form.  The  outline  for  inlay  filling  is  much  the  same  as 
for  other  methods.  Care  should  be  taken  that  the  buccal  and 
lingual  walls  are  parallel,  particularly  the  enamel  portion  of  these 
walls,  as  the  wax  pattern  must  move  directly  to  the  occlusal  sur- 
face in  exit.  It  is  equally  essential  in  inlays  that  angles  and  sharp 
turns  in  outline  be  avoided,  particularly  as  they  will  not  take  in 
the  wax  pattern  and  any  defect  in  the  casting  exaggerates  the 
misfit. 

Resistance  Form.  Flat  gingival  and  pulpal  walls  are  demanded 
in  class  two.  Weakened  buccal  and  lingual  cusps  should  be  re- 
moved and  replaced  with  the  filling  material. 


» 


Fig.   58. — Cavities  of  Class  Two  for  gold  inlays.     Cavity  side  of  inlays  shown.     Black  wax  has 
been  used  in  the  molar  to  temporarily  remove  the  retention  produced  by  decay. 


Retention  Form  is  best  secured  for  vital  cases  by  making  four 
convenience  angles  in  each  case  similar  in  size  to  those  for  co- 
hesive gold.  However,  these  convenience  angles  should  be  laid 
d(nvu  in  the  gingival  and  ])ulj)al  walls  and  cut  entirely  at  the  ex- 
pense of  these  walls  rather  than  at  the  expense  of  the  tooth  substance 
in  the  region  of  the  ascending  line  angles.  To  describe  the  process 
more  accurately  take  a  round  bur,  about  number  one-half  or  iniiii^ 
ber  two,  sink  it  into  the  gingivo-axio-buccal  and  gingivo-axio-lin- 
gual  j)oint  angles  about  the  depth  of  the  bur.  To  this  point  the 
procedure  is  the  same  as  though  we  were  going  to  make  a  con- 
venience angle  for  cohesive  gold.  Instead  of  sinking  the  bur  later- 
ally  into  the  ascendinjj  line  angle  and  drawing  it  occlusally,  as 


104  OPERATIVE    DENTISTRY 

with  cohesive  gold,  we  draw  it  toward  the  mesio-distal  plane  along 
the  gingivo-axial  line  angle,  allowing  it  to  fade  out,  after  going 
once  or  twice  the  width  of  the  bur,  taking  the  tooth  substance 
from  the  gingival  wall.  Treat  both  lower  point  angles  in  this  man- 
ner. In  the  step  portion  of  the  cavity  follow  the  same  procedure 
in  the  two  point  angles,  cutting  all  tooth  substances  at  the  expense 
of  the  pulpal  wall.  This  results  in  giving  the  cavity  draw  to  the 
occlusal  and  giving  your  inlay  four  lugs,  which  key  the  filling  to  a 
seating,  particularly  in  the  region  of  the  gingivo-buccal  and  gin- 
givo-lingual  point  angles.  It  also  results  in  placing  your  retention 
form  high  in  vital  cases  and  near  the  force  of  mastication,  and  in 
a  part  of  a  vital  tooth  which  is  well  suited  to  stand  the  tipping 
strain.     (Fig.  58.) 

In  Non-Vital  Cases  the  retention  form  should  be  placed  low  in 
the  tooth.  In  fact  the  major  portion  of  it  should  be  below  the  gin- 
gival wall,  and  this  is  more  frequently  secured  by  the  use  of  the 
pin  inlay.  When  the  pin  is  not  used,  the  pulp  chamber  is  so  shaped 
that  the  wax  pattern  Avill  show  a  lug,  which  can  be  used  for  the 
major  portion  of  the  retention. 

Finishing  of  Enamel  Walls.  This  part  of  the  cavity  prepara- 
tion should  be  attended  to  with  all  of  the  care  and  detail  that  is 
required  when  making  a  cohesive  gold  filling.  In  addition  there- 
to, after  the  planing  has  been  done  with  a  chisel,  x>articularly 
on  the  buccal  and  lingual  outline,  these  margins  should  be  pol- 
ished with  a  very  fine  grit  disk.  This  facilitates  the  travel  of 
the  wax  on  these  two  surfaces  when  going  to  exit.  A  chisel  fin- 
ish on  these  surfaces,  results  in  a  pattern  that  under  the  micro- 
scope shows  little  fine-projections,  which  have  gone  into  the  rough- 
ened surface.  In  drawing  the  pattern  these  little  projections  have 
been  bent  and  point  gingivally.  This  results  in  an  imperfect  cast- 
ing along  these  surfaces  and  interferes  with  the  fit.  Whereas  if 
the  surfaces  have  been  polished,  a  polished  wax  pattern  results 
and  the  completed  inlay  more  nearly  fits  the  margins. 

When  the  cavity  on  account  of  decay  is  naturally  retentive  or 
has  undercuts  these  are  temporarily  filled  and  overcome  by  cov- 
ering the  retentive  portion  of  the  cavity  with  some  substance,  as 
temporary  stopping  or  wax  of  a  different  color  than  that  used 
in  making  the  pattern. 

Preparation  of  Cavities  of  Class  Three. 

The  gold  inlay  is  seldom  indicated,  in  cavities  of  Class  Three. 


CAVITY  PREPARATION  FOR  GOLD  INLAYS 


105 


All  exception  may  be  made  in  those  Avhieh  are  lary:e  and  have 
thrcniuh  decay  lost  their  entire  lingnal  wall. 

Access.  It  is  of  a  necessity  from  the  lingual  as  Class  Three 
cavities  receive  their  stress  from  that  direction. 

The  Outline  is  the  same  as  though  a  cohesive  filling  "were  to  be 
made.  Care  should  be  taken  that  the  labial  level  is  laid  on  the 
same  plane  as  the  travel  of  the  wax  pattern  to  exit,  else  this  por- 
tion of  the  model  will  l)e  distorted  in  removal. 

The  Gingival  Wall  Should  Meet  the  axial  Avail  at  an  acute  an- 


Fig.  59. — Cavity  of  Class  Three  for 
gold  inlay,  lingual  approach.  Cavity  side 
of   inlay   shown. 

gle  and  the  cavity  should  liave  a  1 
axio-incisal.  •  The  labio-axial  line 
than  the  outline  of  the  cavity  wh 
gual  surface.  This  will  result  in 
lingual.  As  the  labial  wall,  which 
care  should  be  taken  that  it  is  w 
else  the  seating  of  the  iiilav  will 


Fig.     60. — Inlay    shown    in 
in   place. 


Fig.     59    partly 


ine  angle  which  might  be  termed 
angle  should  be  slightly  shorter 
ere  the  axial  Avail  meets  the  lin- 
allowing  the  pattern  exit  to  the 
is  the  seat  of  the  cavity,  is  frail, 
ell  supported  by  sound  dentine, 
cause  fracture  of  this  Avail. 


Preparation  of  Cavities  of  Class  Four. 

The  u.se  of  the  inlay  sliould  be  largely  restricted  to  non-vital 
ca.ses  and  a  ])iii  in  the  pulp  canal  used  for  the  major  portion  of 
leteiilion. 

If  the  Inlay  is  used  in  Class  Four  plans  one  and  Ihree,  the  case 


106 


OPERATIVE   DENTISTRY 


sliould  always  be  devitalized.     In  vital  cases   the  inlay  may  be 
used  to  advantage  in  plans  two  and  four. 

Resistance  Form.     In  this  part  of  cavity  procedure  the  same 
care  should  be  exercised  as  when  using  the  cohesive  gold  filling. 


Fig.  61. — Cavity  of  Class  Four,  plan  one,  for  gold  inlay.     Cavity  side  of  inlay  shown. 


Fig.  62. — Class  Four,  plan  one,  inlay  in  position.     Cavity  shown  in  Fig.   61. 

This  is  particularly  true  at  the  incisal  edge,  where  the  beveling  to 
the  axial  should  be  quite  generous  to  protect  against  breaking 
down  of  this  margin  due  to  the  fact  that  stress  comes  at  right 
angles  to  the  long  axis  of  the  enamel  rods. 


CAVITY    PREPARATION    FOR    GOLD    INLAYS 


107 


Retention  Form.  This  step  in  cavity  procedure  will  vary  ac- 
cording to  Avhich  plan  of  Class  Four  is  used.  In  plan  one,  which 
as  before  stated  should  be  used  only  in  non-vital  cases,  a  pin 
should  be  placed  in  the  pulp  canal  and  depended  upon  almost  en- 


Fig.  63. — Cavity  of  Class  Four,  plan  two,  for  gold  inlay.     Cavity  side  of  inlay  shown. 
wax   has   been   used   to   temporarily   remove   undercuts   caused   by   decay. 


Black 


Fig.  64. — Class  Four,  plan  two,  gold  inlay  in  position.     Cavity  shown   in  Fig.   63. 


tirely  for  tlie  rctenti<jii.  Ju  plan  two,  largely  used  in  vital  cases, 
a  short,  20-gauge  pin  of  iridio-platinum  or  tungsten  should  be 
placed  in  the  step  portion  of  the  cavity  lying  parallel  to  the  long 
axis  of  the  tooth.     This  small  pin  had  best  be  from  one  to  three 


108 


OPERATIVE   DENTISTRY 


millimeters  long,  owing  to  the  possibilities  of  the  case.  The  gin- 
gival retention  may  be  accomplished  either  by  using  a  similar  pin 
to  that  used  in  the  incisal,  placing  the  hole  for  same  in  about 
the  center  of  the  gingival  wall,  or  the  plan  of  retention  used  in 
the  eino-ival  wall  Class  Two  may  be  used.     This  consists  in  cut- 


Fig.  65. — Cavity  of  Class  Four,  plan  three,  for  gold  inlay.     Cavity  side  of  inlay  shown. 


Fig.   66. — Class  Four,  plan  three,  inlay  in'  position.      Cavity   shown  in   Fig.   65. 


ting  the  two  convenience  angles  in  the  gingival  wall.  In  plan 
three,  non-vital,  the  pin  in  the  root  canal  should  be  used.  In  plan 
four  same  retention  used  as  in  plan  two  as  the  case  is  nearly  al- 
ways vital. 

The  Enamel  Walls   should  be  well  beveled,   which  will   in  no 


CAVITY    PREPARATION    FOR    GOLD    INLAYS 


109 


way  hinder  the  removal  of  the   model.     Model  should  make   exit 
to  the  ineisal  with  a  slisht  lingual  travel. 


Fig.    67. 


Fig.   68. 


Fig.  67.— Cavitv  of  Class  Four,  plan  four,  for  gold  inlay.  T'.lack  wax  has  been  spread  on 
the  labial  wall  before  making  the  pattern  to  prevent  the  gold  from  touching  this  wa  when 
setting  the  inlav  for  two  reasons.  First:  It  removes  liability  of  fracture  of  this  wall  when 
setting  the  inlav.  Second:  This  wax  is  replaced  with  cement  and  the  color  of  the  tooth  is 
preser°ved.  The'  wire  loop  secures  the  alinement  of  the  two  posts  and  facilitates  handling  the 
pattern.  When  the  wire  is  not  entirely  buried,  platinized  gold  should  be  used.  When  it  is 
entirely  buried  tungsten  may  be  used. 

Fig.  6g. — Class  Four,  plan  four,  showing  cavity  side  of  pattern  with  pins. 


Fig.    69. — Class    Four,    plan    four,    inlay    in    position    before    removing    wire    loop.      Cavity    and 
pattern  shown  in   Figs.  67  and  68. 

Preparation  of  Cavities  of  Class  Five. 

Oi"  this  ola.ss  llie  hirye  Imccal  cavil  ies  eall  for  <i()ld  inlays,  in 
which  they  are  the  ideal  filliiiu',  Jnid  should  largely  r('i)lacc  amal- 
irain  so  commonly  used. 


110 


OPERATIVE    DENTISTRY 


The  Occlusal  Wall.  The  axio-occlusal  angle  should  be  slightly 
obtuse,  while  the  axio-mesial  and  distal  angles  may  be  nearly  a 
right  angle.  This  will  permit  the  model  to  tip  to  the  buccal  in 
exit,  though  the  gingivo-axial  angle  be  acute. 

Preparation  of  Cavities  of  Class  Six. 

The  restoration  of  abraded  surfaces  with  the  gold  inlay  is  good 
practice,   inasmuch  as   it  is   possible   to   effectually  protect  these 


Fig.    70. — Class   Five   cavity   and   inlay. 


Fig.   71. — Showing  the  necessary  amount  of  metal  for  adequate  protection  of  abraded  surfaces, 

when  opening  the  bite. 

surfaces  from  further  destruction  with  the  minimum  amount  of 
cutting.    As  is  the  case  with  the  other  forms  of  filling  the  surface 


CAVITY   PREPARATION   FOR   GOLD   INLAYS  111 

covered  should  be  generous.  If  only  one  tooth  is  to  be  treated 
with  this  filling  the  amount  of  tooth  substance  cut  away  will  be 
about  the  same  as  the  quantity  of  gold  in  the  inlay. 

However  if  the  bite  is  to  be  raised  on  most  or  all  teeth  the  cut- 
ting should  be  very  slight  and  only  enough  to  properly  cleave 
and  bevel  the  enamel  margins. 

In  vital  cases  either  incisal,  lingual  or  occlusal,  the  retention 
should  be  made  by  the  introduction  of  short  pins,  iridio-platinum 
or  tungsten  preferred,  through  a  matrix  of  pure  gold,  and  then 
casting  the  contour. 

In  Non-Vital  Cases  a  single  large  pin  should  be  used,  or  the 
model  may  be  so  made  as  to  occupy  a  part  of  the  pulp  chamber 
in  lieu  of  the  pin. 


PART  II 

CHAPTER  XIX. 
THE  MAKING  AND  SETTING  OF  A  GOLD  INLAY. 

Ill  discussing  the  methods  of  making  any  filling,  particularly 
the  gold  inlay,  one  must  bear  in  mind  that  the  best  practice  today 
may  be  obsolete  tomorrow.  In  this  chapter  an  attempt  is  made 
to  bring  out  only  the  most  popular  methods  at  this  time,  as  we 
are  fully  aware  that  new  methods  are  continually  being  devised, 
Avhich  may  prove  of  better  service.  In  fact,  since  placing  the  first 
edition  of  this  book  on  the  market,  there  have  been  material 
changes  in  methods,  which  have  resulted  in  much  improvement 
in  this  class  of  fillings.  However,  it  is  a  question  in  the  minds  of 
most  of  our  prominent  teachers,  as  to  the  comparative  value  of 
this  method  when  considering  the  cohesive  gold  filling.  If  the 
excellent  results  obtained  in  the  use  of  cohesive  gold  are  to  be 
approached  in  the  use  of  the  inlay,  great  care  and  pains  must 
be  taken  with  every  little  detail. 

The  Object  of  the  Inlay.  The  object  of  the  inlay  is  to  protect 
the  cement  which  covers  the  cavity  Avails  and  restore  lost  contour. 

If  cement  were  permanent  in  the  mouth  when  exposed  to  wear 
and  dissolving  agents,  there  would  be  no  call  for  inlays,  which 
are  really  only  made  to  protect  the  cement.  It  is  therefore  of  the 
utmost  importance  that  the  inlay  completely  cover  the  cement  by 
a  perfect  adaptation  at  the  cavity  margins  and  that  it  be  so  con- 
structed that  it  will  maintain  this  close  adaptation. 

In  choosing  the  method  of  construction  in  each  case  the  mar- 
ginal adaptation  should  be  considered  and  the  one  selected  which 
promises  the  greatest  perfection. 

History.  The  gold  inlay  is  one  of  the  oldest  forms  of  filling. 
In  fact,  it  is  the  oldest,  as  proved  by  excavations  in  the  Orient. 
Teeth  in  the  skulls  of  mummies  have  been  found  wherein  cavities 
have  been  crowded  full  of  lead,  with  the  probable  intent  to  cheek 
decay.  Even  in  modern  times  the  inlay  has  always  been  prac- 
ticed more  or  less,  and  has  become  more  popular  as  time  goes  on. 
As  compared  with  the  making  of  a  cohesive  gold  filling,  it  is  in- 
finitely easier,  and  the  history  of  our  college  clinics  shows  that 
the  beginner  attains  a  passing  degree  of  success  with  the  gold  in- 

112 


MAKING    AND    SETTING    OF    A    GOLD    INLAY 


113 


lay  long  before  he  is  able  to  understand  and  successfully  bring- 
to  bear  many  of  the  qualities  of  cohesive  gold. 

Method  Using-  Pattern  Entirely  of  Wax.  The  cavity  should  be 
prepared  as  for  any  other  metal  filling  except  that  the  retention 
form  should  be  omitted.  In  case  decay  has  so  left  the  cavity  that 
it  is  naturally  retentive  by  having  excavated  undercuts  these  should 
be  filled  with  some  substance  which  does  not  become  a  part  of 
the  pattern,  and  which  is  easily  removed  before  setting  the  in- 
lay. The  substances  used  to  temporarily  remove  the  retentive 
form,  are  cement,  temporary  stopping,  modeling  compound  and 
wax,  the  preference  being  with  the  wax. 

This  Avax  should  be  of  a  decidedly  different  color  than  that  of 
which  the  pattern  is  made.     (See  Fig.  72.) 


Fig.  12. — Large  restoration  in  non-vital  case.  Part  of  the  pulp  chamber  has  been  filled 
with  black  wax  to  remove  undercut  caused  by  pulp  removal.  The  weak  buccal  wall  has  been 
covered  with  the  same  rraterial  to  protect  it -from  stress  from  within  when  setting  the  inlay. 
It  goes  without  saying  that  this  wax  is  all  removed  before  setting  the  inlay  and  is  therefore 
replaced  with  the  cement  with  which  the  inlay  is  set. 


The  Filling-  of  the  Undercuts  should  be  made  to  dry  cavity 
walls,  and  with  the  wax  (juile  warm  to  insure  its  adhering,  that 
it  may  not  leave  the  walls  to  distort  the  ])atteni.  The  dift'erence 
in  the  color  of  Avax  used  will  cause  the  detection  of  any  particles 
Avhich  may  adhere  to  the  pattei-n   and   make   their  removal    easy. 

By  a  little  study  and  the  judicious  use  of  the  al)ove  method 
much  cutting  for  convenience  foi-m  may  l)e  obviated  and  many 
seemingly  difficult  eases  rendei-ed  quite  simple. 

The  Making  of  the  Pattern.  After  the  retentive  form  has  been 
lernoved,  the  cavity  should  be  flooded  Avith  water  of  ordinary 
teniperature.     This   will   render  the  wax   within   the   cavity  suffi- 


114  OPERATIVE   DENTISTRY 

ciently  hard  not  to  yield  under  the  force  necessary  to  introduce 
the  pattern  wax.  It  will  also  prevent  the  portions  of  wax  from 
adhering.  The  wax  for  the  pattern  should  then  be  softened,  pref- 
erably in  warm  water.  The  wax  should  be  sufficiently  plastic  to 
permit  of  molding  when  manipulated  in  the  fingers,  care  being 
taken  that  the  wax  is  not  folded  upon  itself  as  the  portions  will  not 
adhere.  Wax  so  folded  is  liable  to  part  at  the  folds  and  come  away 
from  the  cavity  in  sections.  The  wax  should  be  gently  shaped  so 
that  it  can  be  introduced  into  the  cavity  in  such  manner  as  to  come 
in  contact  with  the  base  walls  or  floor  of  the  cavity  first,  then  by 
sloAv  continued  pressure  for  about  fifteen  seconds  made  to  expand 
till  it  entirely  fills  the  cavit)',  overflowing  all  margins. 

If  the  inlay  is  to  replace  any  portion  of  the  occluding  surface  the 
operation  should  be  done  with  the  rubber  dam  off.  The  patient  is 
requested  to  close  the  teeth  to  full  occlusion,  slowly.  It  must  be 
remembered  that  the  casting  wax  is  only  semi-plastic  and  moves 
very  slowly,  hence  the  best  impression  is  obtained  by  moderate  con- 
tinued force,  giving  the  sluggish  wax  time  to  flow.  ^Yax  is  really 
quite  elastic  when  confined  and  when  the  pressure  from  the  bite 
is  removed  will  spring  back  the  least  bit,  so  that  the  cast  inlay  will 
be  too  high  when  set. 

To  overcome  this  it  is  good  practice  to  have  the  patient  again  close 
the  teeth  to  occlusion  with  one  layer  of  rubber  dam  over  the  occlu- 
sal surface  of  the  model,  requesting  him  to  inaintain  the  pressure 
for  some  seconds.  The  elasticity  of  the  rubber  dam  will  overcome 
the  elasticity  of  the  wax.  This  will  do  aAvay  with  much  grinding 
after  fitting  the  inlay  to  position.  The  pattern  should  then  be  carved 
to  full  contour  restoration  and  correct  external  surface  form,  and 
the  wax  thoroughly  burnished  around  the  entire  cavity  outline. 

The  carving  and  burnishing  of  the  wax  is  materially  assisted 
if  the  surface  is  warmed  by  the  use  of  warm  water.  This  is  best 
accomplished  by  dipping  large  loosely-rolled  cotton  balls  in  water 
that  is  almost  too  warm  for  the  fingers,  carrying  it  to  the  mouth 
and  folding  about  the  wax,  allowing  it  to  remain  for  a  few  seconds. 
Upon  removing  the  cotton  the  wax  will  be  found  to  have  softened 
to  a  sufficient  depth  to  be  easily  manipulated.  In  case  the  wax  does 
not  quite  reach  the  margin,  the  same  should  be  crowded  over  to 
the  margins,  carrying  quite  a  body  of  the  wax  over  before  attempt- 
ing to  burnish  down  to  the  margins.  If  this  is  not  done  the  wax 
will  be  found  to  fit  only  at  the  cavo-surface  angle,  leaving  a  space 
just  below  this  point  to  which  the  wax  is  not  adapted. 


MAKIN'C    AND    SETTING    OF    A    GOLD    IXLAY 


115 


Ideal  Conditions  Are  Obtained  when  the  Max  slis^htly  overlaps 
the  eavo-siirfaee  aiigle  at  all  points  in  the  outline,  al)Out  one-tenth 
of  a  niillinietei-. 

This  Avill  ofive  .sufficient  l)ulk  for  correct  finishiii<;.  After  the  com- 
pletion of  the  pattern  it  is  well  to  insert  the  tine  of  an  explorer 
to  the  depth  of  about  one  or  two  millimeters  in  a  convenient  posi- 
tion for  removal. 

The  tine  should  be  removed  and  the  pattern  chilled  with  cold 
water,  the  tine  reinserted  into  the  previously  made  hole,  the  pat- 
tern gently  pushed  to  exit  and  then  given  a  cold  water  bath. 

The  Placing-  of  the  Sprue  Wire.  While  the  pattern  is  still  carried 
on  the  tine  of  the  explorer,  the  sprue  wire  should  be  warmed  and 
inserted. 

The  sprue  wire  should  be  very  fine,  preferal)ly  copper,  and  in- 
troduced deep  into  the  pattern.     This  use  of  a  fine  sprue  Avire  is  of 


Fig.    73. — Some  of  the  methods  by   which  inlays  may  be  given   retentive   form   in  large  decays 

and   non-vital  cases. 


advantage  from  the  fact  that  no  considerable  body  of  the  wax 
melts  and  runs  back  up  the  wire  to  produce  a  concavity,  close  to 
where  the  wii-e  is  in1  rodnccd,  A\hich  liaj)i)(Mis  when  a  large  sprue 
Avire  is  used. 

In  selecting  the  ])osilioii  foi-  ihe  Avire,  eai'c  should  be  Inken  tliat 
a  location  is  chosen  so  that  the  contour  of  1lie  surface  of  the  pattern 
leaves  the  spi-ue  Avire  in  all  directions  at  an  obtuse  angle.  A  neglect 
of  this  point  Avill  occasionally  result  in  iiii])erfect  casts  near  the 
sprue  former.  The  tine  of  the  explorer  should  now  be  AvithdraAvn 
and  the  resulting  hole  sealed  by  1oneliin<i-  \\i1li  1li(^  ^va]•nl  end  of 
a  small  instrument. 

A  good  instrument  for  sucli  work  is  1lie  lljillened  end  oj'  a  bn'ge 
f;inal  cleaner'  or  hrojieli.  nionnled  on   a   wooden  handle. 

Giving-  the  Wax  Pattern  Retention  Form.     Tortions  of  the  pat- 


116  OPERATIVE    DENTISTRY 

tern  should  now  be  removed,  preferably  by  the  use  of  the  heated 
hollow  needle,  in  such  manner  as  to  give  the  cement  an  ample  grasp 
upon  the  inlay,  and  should  be  equal  to  or  more  than  the  amount 
-of  retention  of  which  the  cavity  in  the  tooth  is  capable.  The  pat- 
tern is  then  ready  for  investment. 

Method  of  Using  Wax  Pattern,  Pin  Attached.  This  method  is 
of  service  when  for  any  reason  it  is  desired  to  have  the  maximum 
amount  of  retention.  In  such  cases  the  tooth  Avill  generallj^  be  non- 
vital  and  a  portion  of  the  pulp  cavity  used  for  the  reception  of 
the  pin. 

Placing  the  Pin.  The  cavity  should  be  first  freed  from  retentive 
form  as  described  above,  using  either  cement,  temporary  stopping, 
modeling  compound,  or  wax,  then  the  opening  made  in  the  root 
canal  to  receive  the  pin  which  is  placed  in  position,  with  a  light 
coat  of  sticky  wax  on  the  outer  end.  The  pin  should  be  long  enough 
to  reach  well  into  the  body  of  the  wax  pattern  and  should  be  iridio- 
platinum,  platinized  gold  or  tungsten.  These  materials  will  stand 
the  heat  of  casting  the  inlay  without  alloying  or  losing  their  rigidity. 

Tungsten  Pins.  The  use  of  tungsten  in  casting  gold  inlays  is  of 
great  advantage,  as  this  material  is  easily  cast  upon  when  the  wire 
has  been  previously  gold-plated.  The  wire  is  about  six  times  as 
strong  as  iridio-platinum  of  the  same  gauge  and  three  times  as  strong 
as  steel.  This  material  does  not  lose  its  temper  upon  being  heated. 
It  therefore  gives  us  a  very  rigid  pin  in  the  completed  work.  As  the 
gold  will  not  cast  to  the  end  of  the  pin,  which  has  been  cut  off  and 
is  not  gold-plated,  it  is  very  essential  that  these  exposed  ends  be 
well  buried  in  the  wax,  which  can  be  accomplished  by  seeing  that 
the  pin  does  not  come  near  the  surface  of  the  casting,  or  else  that 
the  end  is  bent  so  as  to  throw  the  exposed  surface  more  deeply  into 
the  wax  pattern.  With  the  pin  in  position  in  the  cavity  the  wax 
for  the  pattern  is  manipulated  the  same  as  though  no  pin  had  been 
used.  "When  the  pattern  is  withdrawn  the  pin  should  come  away 
with  the  wax.  In  case  it  does  not,  withdraw  the  pin  from  the  tooth 
and  seal  it  into  the  hole  it  has  left  in  the  wax  pattern  and  return 
to  position  to  insure  alignment.  Withdraw  the  pattern  after  chill- 
ing and  all  is  ready  for  investment. 

Method  of  Using  Pure  Gold  Matrix  With  Pin  Soldered  on, 
Casting  the  Contour.  This  method  is  advised  as  most  practical  in 
cavities  of  Class  Four  (first  plan),  when  teeth  are  non- vital,  in  in- 
eisal  restorations  vital  or  non-vital,  in  occlusal  restorations,  cavities 
•of  class  six  particularly  in  vital  cases,  and  in  lingual  restorations. 


MAKING    AND    SETTING    OF    A    GOLD    INLAY  117 

"With  these  lingual  restorations,  the  amount  of  surface  covered  is 
generally  quite  large  as  compared  to  the  thickness  of  the  restoration 
vrhich  is  best  termed  an  "onlay." 

This  method  simplifies  angle  restoration  in  (lass  Four  plan  one 
and  provides  ample  resistance  form,  without  the  cutting  of  either 
the  ineisal  or  lingual  step.  In  such  eases  the  alignment  of  the  pin 
must  be  perfect  else  the  inlay  Avill  not  go  to  proper  place.  The 
soldering  of  the  pin  to  a  gold  matrix  gives  the  desired  security  during 
the  processes  of  removing  and  investment.  The  cavity  preparation 
is  the  same  as  for  cohesive  gold  except  the  convenience  angles. 
The  pin  is  fitted  to  a  portion  of  the  root  canal  as  previously  given. 
A  sheet  of  pure  gold,  S2  to  34  gauge  is  selected  of  sufficient  size  to 
more  than  cover  the  cavity  by  about  two  millimeters.  This  is  par- 
tially burnished  to  the  cavity,  enough  to  show  the  cavity  outline 
in  the  gold.  A  hole  is  punched  in  the  proper  position  to  receive  the 
pin,  but  smaller  than  the  pin,  which  should  be  15  or  16  gauge.  In 
case  the  inlay  is  to  be  used  as  an  abutment  for  a  bridge,  the  pin  had 
better  be  as  large  as  14  gauge,  if  platinized  gold  is  used.  When 
tungsten  is  used,  IG  gauge  is  amjjle. 

The  operator  should  then  place  the  matrix  in  position  and  crowd 
the  pin  through  the  hole  to  place ;  then  scribe  the  pin  just  external 
to  the  gold  matrix,  remove  and  solder  as  nearly  in  correct  position 
as  possible,  without  stopping  to  invest,  using  22K  solder. 

Only  a  very  small  amount  of  solder  will  be  needed  or  should  be 
used,  care  being  taken  that  it  is  all  flowed  close  to  the  pin  to  pre- 
vent stiffening  the  matrix.  All  should  then  be  returned  to  the 
eavit}^  and  the  gold  reljurnished  to  a  perfect  fit  of  the  entire  cavity 
outline. 

It  is  necessary  to  burnish  the  gold  only  partially  into  the  deep 
recesses  of  the  cavity  as  the  pin,  if  of  iridio-platinum  or  tungsten, 
will  be  sufficient  anchorage.  This  can  be  made  to  equal  that  fre- 
quently relied  on  for  an  entii*e  crown.  This  pattern  must  move  to 
the  ineisal  for  exit  and  if  the  matrix  is  Ijui'iiislicd  to  contact  with 
the  axial  wall  it  will  become  fixed.  The  matrix  should  be  bur- 
nished to  a  complete  fit  of  the  gingival  Avail  which  should  be  flat 
and  well  sfjuai-ed  into  Ihc  l;il)i;il  and  lingual  angles. 

Making  the  Wax  Contour.  The  matrix  and  attached  pin  are  re- 
iiKAcd,  and  the  dcsiied  contoui'  built  up  by  flowing  the  wax  to 
position  Avith  a  spatula,  trying  the  anIioIc  ])at1('rn  1o  ])lace  in  the 
cavity  to  guide  in  the  restoration.  When  coni])lote,  the  Avax  is 
chilled  and  removed  and  all  is  readv  for  investment. 


118  OPERATIVE    DENTISTRY 

To  Restore  Occlusal  and  Incisal  Surfaces  lost  from  abrasion 
with  inlays  where  the  tooth  is  vital,  nothing  answers  the  purpose 
better  than  the  following  method.  The  outline  of  the  surface  .to 
be  covered  is  established.  Small  holes  are  drilled  to  convenient 
depths  in  safe  locations  of  sufficient  size  to  receive  a  20  gauge 
iridio-platinum  or  tungsten  pin.  Three  or  four  pins  are  required 
for  molars  and  two  or  three  for  bicuspids  or  incisors.  A  pure  gold 
matrix,  32  or  34  gauge,  is  then  burnished  to  an  approximate  fit. 
The  positions  of  the  holes  in  the  tooth  Avill  be  outlined  in  the  gold. 
The  matrix  should  be  pricked  at  these  points  with  a  sharp  pointed 
instrument  smaller  than  the  pins.  One  pin  is  inserted  and  should 
l)rotrude  occlusally  through  the  matrix  for  a  short  distance,  and 
be  bent  at  rigbt  angles. 

It  is  good  practice  when  using  tungsten  to  make  a  loop  which 
goes  to  the  full  depth  of  two  of  the  holes  and  lies  along  the  gold 
surface  in  the  body  of  the  loop,  thus  establishing  the  alignment  of 
two  -of  the  pins  at  once.  This  also  places  the  exposed  end  of  these 
tungsten  pins,  to  which  gold  Avill  not  cast,  entirely  away  from  a 
position  which  might  result  in  showing  the  exposed  ends  in  the 
completed  case. 

This  pin  and  matrix  are  then  removed  and  attached  with  solder, 
applying  the  solder  to  the  occlusal  side  of  the  matrix.  The  matrix 
should  be  i-eturned  to  the  tooth  and  another  pin  placed  and  at- 
tached in  the  same  way,  repeating  until  all  pins  are  in  position, 
when  the  matrix  should  receive  a  final  burnishing.  The  wax  con- 
tour is  then  added  as  before  described,  the  pattern  replaced  and 
articulation  secured  in  the  mouth  and  finally  trimmed  to  desired 
contour.  The  wax  should  then  be  chilled  and  the  entire  pattern 
removed  and  invested. 

Method  of  Sweating  the  Contour. — Advantages.  The  advan- 
tages of  this  older  method  of  making  an  inlay  still  exist  Avhere  the 
inlay  is  to  cover  considerable  surface  and  is  very  shallow.  Such 
inlays  are  generally  termed  "onlays."  This  method  is  advised 
from  the  fact  that  models  of  such  nature  will  seldom  maintain  ex- 
act form  during  the  process  of  removing  and  investment  unless  a 
gold  matrix  is  used. 

If  the  gold  matrix  is  used  it  is  difficult  to  cast  a  thin  layer  of 
gold  over  the  entire  surface  of  this  matrix  and  get  good  margins 
unless  a  large  quantity  of  gold  is  melted  to  make  the  cast  in  which 
ease  the  gold  matrix  is  very  liable  to  be  entirely  fused,  which  will 
not  give  the  best  results.     Speed  is  also  a  factor  in  this  instance. 


MAKING    AND    SETTING    OF    A    GOLD    INLAY  119 

Many  times  an  onlay  can  be  floAved  to  the  desired  thiekness  in 
much  less  time  than  that  required  to  invest  and  east. 

Making-  the  Matrix,  This  is  done  in  the  same  way  as  though  a 
greater  bulk  of  gold  -were  to  be  added.  Such  inlays  must  be  re- 
tained by  one  or  more  pins  soldered  to  the  cavity  side  as  pre- 
viously described. 

The  matrix  is  burnished  to  perfect  fit  and  the  outline  definitely 
established.  The  matrix  should  be  trimmed  to  within  about  one- 
fourth  millimeter  of  the  cavity  outline  and  re])urnished  and  care- 
fully removed. 

The  matrix  is  then  given  a  coat  of  whiting  on  all  that  portion 
which  is  to  come  in  contact  with  the  tooth  to  prevent  the  solder 
from  flowing  on  that  surface. 

Sweating-  the  Contour.  The  gold  matrix  should  be  then  laid 
upon  the  soldering  l)lock  and  with  a  brush  flame  from  the  blow 
])ipe  22K  plate  or  22K  solder  fused  to  the  thickness  desired  in  the 
"\  arious  locations  on  the  matrix.  "When  a  sufficient  amount  has 
been  fused  in  any  portion,  that  part  of  the  surface  should  receive  a 
coat  of  whiting. 

Gold  can  then  be  fused  to  still  exposed  surface  without  its 
spreading  to  portions  where  it  is  not  wanted.  By  this  means  it  is 
possible  to  build  up  a  given  portion  of  the  inlay,  even  to  the  add- 
ing of  cusps  to  occlusal  surfaces. 

Method  of  Using-  Sponge  Gold  as  a  Pattern.  Take  the  sponge 
gold  as  bought  on  the  market  for  making  a  cohesive  gold  filling 
and  satui-ate  it  with  any  casting  wax  on  the  market.  This  is  best 
accomplished  by  dipping  a  sufficient  amount  of  the  heated  gold, 
"while  held  in  the  pliers,  into  the  molten  wax,  and  innnediately  re- 
moving to  a  clean  surface  to  cool.     Kemove  any  excess  Avax. 

Making  the  Pattern.  AVhen  this  method  is  used  any  undercuts 
in  the  cavit\-  should  be  filled  with  cement.  A  portion  of  the  satu- 
rated gold  large  enough  to  a  little  more  than  fill  the  cavity  is 
grasped  between  the  pliers  and  slightly  warmed  and  cari'ied  to  the 
cavity  and  crowded  to  position  and  the  contour  determined  in 
much  the  same,  way  as  amalgam  is  manipulated.  A  matrix  should 
be  used  in  class  two  cavities,  but  not  sufficiently  high  to  prevent 
occluding  the  teeth.  AVhen  the  })at1ei-n  has  the  desii'cd  contour 
form,  the  whole  is  removed  the  same  as  desci-ibed  foi-  lemoving  a 
pattern  comi)oscd  of  A\ax  alone. 

Investing".  A  spi-ue  of  wax  is  attached  to  the  usual  place  as 
Ihonudi   tlie  casting  method  were  to  be  used.     The  pattern  is  then 


120  OPERATIVE   DENTISTRY 

submerged  in  much,  the  same  way  as  a  tooth  is  invested  to  have  a 
backing  flowed  but  sufficiently  deep  upon  the  wax  sprue  former  to 
leave  upon  its  removal  a  receptacle  for  the  gold  solder  to  be  fused. 

Saturating  the  Model.  Heat  may  be  applied  to  the  invested  pat- 
tern as  soon  as  the  investment  has  set,  and  the  wax  gradually 
burned  out  leaving  a  framework  of  pure  gold  filling  the  mold. 
Then  scraj)s  of  22K  gold  plate  are  placed  in  the  hole  left  by  the 
sprue  former  and  all  is  heated  to  the  point  of  fusing  the  22K  gold 
which  will  disappear  through  the  opening  and  completely  saturate 
the  pure  gold  within  the  mold.  The  inlay  may  be  immediately 
chilled  and  finished.  This  method  has  to  recommend  it,  speed  of 
manipulation,  and  is  indicated  in  large  contour  restorations,  where 
it  is  desired  to  use  a  solid  inlay. 

.  Making  the  Cast.  Generally  considered  we  have  three  forces 
used  in  placing  the  gold  in  the  mold;  suction,  pressure,  and  cen- 
trifugal. Centrifugal  force  is  the  only  one  wherein  all  atoms  or 
molecules  of  the  material  are  acted  upon,  and  greater  accuracy  is 
obtained  by  this  method. 

Place  of  Heating  the  Gold.  The  temperature  of  the  mold  at  the 
time  the  gold  strikes  it,  in  casting,  is  of  great  importance.  There- 
fore, the  place  Avhere  the  gold  is  melted  should  not  be  on  the  body 
of  the  investment  over  the  mold,  for  by  that  method  we  are  not 
able  to  vary  the  temperature  of  the  mold  at  the  time  of  casting. 
The  gold  should  be  melted  on  a  separate  tray  and  the  mold  should 
be  heated  to  the  desired  temperature  independently  of  the  material 
being  cast. 

Temperature  of  the  Mold.  By  a  little  experimenting  we  will  be 
able  to  demonstrate  that  a  body  of  molten  gold  contracts  toward, 
first,  that  part  which  is  chilled  first,  second  toward  the  greatest 
body  of  gold;  that  is,  when  the  gold  consists  of  two  parts  con- 
nected by  a  small  isthmus,  or  in  other  words,  pedunculated,  there 
is  a  tendency  for  the  smaller  body  of  gold  to  shrink  toward  the 
larger  one.  The  first  part  of  the  gold  which  we  desire  to  set 
through  the  process  of  chilling  is  that  part  of  the  inlay  which  is 
most  essential  to  a  perfect  fit,  namely  the  margin  or  that  whiish 
covers  the  marginal  bevel  and  second  all  of  the  cavity  walls. 
Therefore,  it  is  important  when  the  gold  is  thrown  into  the  mold 
that  the  investment  which  forms  the  mold  be  of  a  temperature  to 
chill  the  gold  at  first  impact,  bearing  in  mind  that  it  should  be 
warm  enough  to  permit  of  the  gold  to  enter  the  sharpest  recesses. 


MAKING    AND   SETTING    OF   A   GOLD   INLAY  121 

When  Using'  Pin  or  Pure  Gold  Matrix.  AVhen  casting  an  inlay 
to  a  mold  which  contains  a  pin  or  a  pnre  gold  matrix,  the  tem- 
perature of  the  mold  should  be  considerably  higher.  Particularly 
is  this  true  Avhen  the  pin  is  large  or  the  amount  of  gold  to  cover 
the  matrix  is  thin  as  it  may  be  close  to  the  margins. 

Quantity  of  Gold  Used  in  the  Cast.  When  using  the  suction  or 
pressure  machines  it  is  quite  necessary  to  have  a  large  sprue  left, 
as  when  the  amount  of  gold  is  near  the  size  of  the  inlay,  failure  is 
liable  to  result  oAving  to  the  philosophy  of  the  force  used  in  cast- 
ing. However,  with  the  centrifugal  machine,  it  is  not  absolutely 
essential  that  there  be  any  considerable  sprue  left.  Yet  if  we  try 
to  guess  too  closely,  many  failures  will  result  from  having  too  lit- 
tle material.  OAving  to  the  law  of  the  shrinkage  of  the  metal  to- 
wards the  larger  body,  the  sprue  w^hich  is  left  should  never  weigh 
as  much  as  the  inlay  cast.  A  large  sprue  left  is  of  advantage,  as 
there  is  a  tendency  to  hold  the  whole  body  of  gold  at  a  tempera- 
ture sufficient  to  give  it  time  to  thread  its  way  through  the  sprue 
hole  into  the  mold.  It  is  also  of  advantage  where  there  is  a  large 
pin  or  matrix  present,  as  the  high  temperature  is  maintained  longer. 

The  large  sprue  is  particularly  at  a  disadvantage  when  casting 
the  base  to  pin  croAvns.  The  low  fusing  pin  is  liable  to  be  melted. 
There  is  also  more  danger  of  checking  the  porcelain. 

Size  of  the  Opening".  The  size  of  the  hole  leading  to  the  mold  is 
of  importance  for  a  number  of  reasons.  As  a  general  rule  the 
larger  the  inlay,  and  the  lower  temperature  of  both  the  hole  and 
the  material  at  which  you  cast,  the  larger  should  be  the  hole;  it 
necessarily  follows  that  the  hole  should  be  smaller  with  the  reverse 
conditions. 

A  small  hole  lengthens  the  time  required  for  the  stream  of  molten 
gold  to  pass  to  position.  Hence,  if  the  mold  is  cold  and  the  mate- 
rial is  not  extra  warm  in  casting  a  large  body,  the  material  is  lia- 
ble to  become  chilled  and  the  mold  not  entirely  filled.  However, 
if  we  are  casting  a  small  inlay,  in  a  rather  warm  mold  with  the 
gold  extra  hot,  the  small  hole  is  preferable  as  there  is  less  liability 
of  a  backward  shrinkage  of  the  gold  to  the  sprue,  when  cooling. 

Better  results  are  obtained  Avhen  the  wax  pattern  is  immediately 
invested,  burned  out  and  casting  completed  Avithout  alloAving  the 
mold,  either  AA'ith  the  pattern  in  position  or  burned  out,  to  lay  over 
night.  If  it  must  lay  over  night,  it  is  l)est  to  burn  out  the  wax  and 
thoroughly  heat  the  mold,  as  less  cliange  takes  ])lace  thereafter  in 
the  investment.     In  this  connection  vour  attention  is  called  to  the 


122  OPERATIVE  DENTISTRY 

findings  (d  Prothero  in  the  expansion  and  contraction  of  plaster 
paris  in  the  various  periods  following  its  mixture  with  water. 

Finishing'  the  Inlay.  "With  any  of  the  processes  of  making  an 
inlay  there  are  liable  to  be  some  imperfections  Avhich  will  be  seen 
upon  removing  from  the  investment.  If  these  are  on  the  cavity 
side  of  the  inlay  and  are  of  any  considerable  size  it  will  probably 
be  necessary  to  make  a  new  pattern.  If  they  are  only  slight  and 
are  in  the  form  of  little  pedunculated  masses  they  can  generally  be 
removed  Avithout  injury  to  the  filling.  If  the  contour  shows  that 
the  mold  did  not  entirely  fill  the  necessary  amount  to  complete 
contour,  and  the  margin  is  not  in\'olved  it  may  be  sweat  on  using 
a  gold  of  lower  fusing  point  than  that  of  the  inlay.  Another 
method  is  to  make  a  gold  amalgam  and  build  to  the  desired  con- 
tour. Then  the  inlay  should  be  subjected  to  heat  gradually  raised 
to  nearly  red  heat  when  the  mercury  will  be  volatilized  leaving  the 
pure  gold  fused  to  the  position  desired.  This  gold  amalgam  is 
made  by  adding  mercury  to  cohesive  gold  foil,  pellets  or  fiber 
which  have  been  annealed,  mixing  thoroughly  in  the  palm  of  the 
hand  and  applying  immediately  to  place.  All  exposed  surfaces  of 
gold  inlays  should  receive  a  high  polish  before  setting,  omitting 
a  line  about  one-fourth  of  a  millimeter  next  to  the  entire  margin. 

Setting  the  Inlay.  The  inlay  should  l)e  washed  with  water  and 
dried;  then  dipped  in  chloroform  to  remove  any  oil  that  may  have 
adhered  from  the  hands.  The  cavity  should  be  freed  from  all  for- 
eign substance,  given  complete  retentive  form,  bathed  with  chloro- 
form and  alcohol  in  the  order  named  and  the  surface  of  the  cavity 
entirely  covered  with  cement. 

The  inlay  is  given  a  coat  of  cement  on  its  cavity  side  from  the 
same  mix  and  gently  but  firmly  moved  to  position  using  hand  pres- 
sure assisted  by  light  blows  from  the  mallet.  The  inlay  should  be 
subjected  to  pressure  directed  toAAard  the  seat  of  the  cavity  for 
some  minutes  Avhich  Avill  in  a  measure  overcome  the  tendency  to- 
ward displacement  caused  by  the  expansion  of  the  cement.  An  in- 
lay may  be  finished  at  its  margins  Avithin  thirty  minutes  from  set- 
ting, but  it  is  better  if  this  step  is  attended  to  at  a  subsequent 
time. 


CHAPTER  XX. 

.AIAXIPULATIOX  OF  COHESIVE  GOLD  IX  THE  :MAKING  OF 

A  FHLIXG. 

Physical  Properties.  The  physical  pi-ojjerties  most  desired  in  a 
lillino:  are  found  in  cohesive  gold  to  a  greater  degree  tlian  in  any 
other  filling  material,  Avhich  places  it  at  the  head  of  the  list  as  a 
means  of  i-estoring  lost  contour  and  preventing  recurrence  of  de- 
cay. It  is  not  affected  by  the  fluids  of  the  mouth ;  it  may  be  very 
perfectly  adapted  to  the  Avails  of  the  cavity;  the  shrinkage  and  ex- 
pansion range  in  vai-ying  temperature  is  vei-y  slight;  the  cavity 
can  be  filled  immediately  upon  freshly  cut  surfaces  before  they 
liave  been  contaminated,  an  advantage  over  the  fused  inlay;  and 
■when  sufficiently  condensed  it  possesses  a  greater  specific  gravity, 
hence  density,  than  a  fused  inlay  of  pure  gold.  Hammered  gold 
"will  flow  under  sufficient  stress  and  ahvays  in  proportion  to  the 
load,  when  it  ceases  to  flow,  unless  the  load  is  increased — a 
marked  distinction  between  it  and  amalgam.  This  quality  of  gold 
makes  it  possible  to  build  a  filling  which  will  at  once  sustain  the 
force  of  mastication  provided  it  has  received  sufficient  aggregate 
weight  during  the  process  of  introduction.  This  physical  prop- 
erty of  gold  is  also  of  service  in  that  it  does  not  farther  compress 
Avhen  firmly  wedged  between  the  walls  of  living  dentine  Avhich  are 
elastic  and  retain  a  certain  amount  of  residual  elasticity  which 
permanently  grasps  the  unyielding  gold.  Tlie  expansion  and  con- 
traction of  gold  under  the  varying  oi-al  temperatures  is  fully  com- 
pensated for  by  this  i-esidual  elasticity  of  the  dentine  so  that  the 
clcsely  adapted  cohesive  gold  filling  is  at  all  times  in  ijci'fci-t 
adaf)tatioii. 

The  Objectionable  Qualities  of  Gold.  Gold  is  a  good  conductoi- 
of  thermal  changes,  hence  endangei-s  the  health  of  \ital  ])ulps.  The 
color  is  an  objection  in  anterioi-  positions,  and  the  pi-ocess  of  build- 
ing a  filling  is  comparatively  slow  and  taxing  on  patient  and 
operator. 

Welding  of  Gold.  Gold  welds  cold  when  ])ro|)ei'ly  prepared,  is 
absolutely  i)ure,  and  the  contacting  sui'faces  ai-e  clean.  Any  alloy 
in  its  sub.stance  (excepting  platinum)  or  foreign  substance  upon 
ils  surface  totally  destroys  this  (|uali1y,  unlil  such  substances 
are   removed,   when    the    proj)crty   of    \>('lding   cold   again    rctui'us. 


124  OPERATI\'E   DENTISTEY 

If  tlie  Surface  of  Foil  Becomes  contaminated  with,  a  non-evapor- 
able  substance  the  injury  is  permanent. 

To  Protect  tlie  Surface  of  Gold.  Place  in  the  drawer  where  the 
gold  is  kept  a  small  pledget  of  cotton  or  spunk  saturated  with  am- 
monia. 

Ammonium  salts  will  form  on  the  surface  of  the  gold,  which  are 
easily  volatilized  b^'  heat,  leaving  the  gold  clean.  Before  anneal- 
ing such  gold  will  be  found  thoroughly  non-cohesive.  This  meth- 
od of  treating  the  gold  to  the  fumes  of  ammonia  will  obviate  the 
necessity  of  keeping  more  than  one  kind  of  gold  on  hand,  as  all 
will  be  non-cohesive  till  annealed  and  can  be  used  in  either  form. 

Annealing"  Gold  is  for  the  sole  purpose  of  cleaning  the  surface 
of  the  gold  by  volatilizing  any  film  that  may  have  collected. 

The  Degree  of  Heat  is  about  1100°F.,  or  just  below  red  heat. 

In  the  daylight  this  color  is  not  apparent,  but  on  a  dark  day 
the  dull  red  color  should  show.  The  gold  is  not  materially  injured 
if  carried  to  the  full  red  of  1200  or  1300  degrees,  but  in  no  case 
should  the  melting  point  be  reached,  as  it  destroys  the  possibility 
of  adaptation  to  the  walls  of  the  cavity,  or  the  surface  of  the  gold 
already  in  place. 

Methods  of  Annealing.  The  electric  annealer  is  by  far  the  most 
satisfactory  means,  as  it  is  possible  to  always  obtain  the  same  de- 
gree of  heat  for  a  continued  period. 

Tlie  Next  Best  Means  is  to  place  the  gold  on  a  tray  above  a  flame, 
thus  separating  the  flame  from  the  gold,  preventing  contamination 
of  the  gold  with  carbon,  and  various  gases  which  are  frequently  met 
with  in  combustion. 

Gold  SJiould  Not  Be  Annealed  hy  Passing  It  TJirougli  tlie  Open 
Flame  of  either  gas  or  alcohol,  holding  the  gold  either  on  a  plug- 
ger  point  or  the  foil  carriers.  This  is  quite  a  common  practice, 
which  should  be  discontinued.  In  the  first  place,  heating  the  gold 
with  the  open  flame  frequently  contaminates  its  surface,  to  the 
injury  of  its  welding  properties. 

Also  that  portion  of  the  gold  next  to  the  carrier  is  not  sufficient- 
ly heated  and  remains  non-cohesive,  a  fact  which  is  shown  by  the 
subsequent  pitting  of  the  surface  of  the  filling  during  service  by 
the  flecking  off  of  these  non-cohesive  particles. 

Specific  Gravity.  The  specific  gravity  of  the  cast  gold  inlay  is 
about  19,  varying  the  fraction  of  a  point. 

It  is  possible  to  condense  a  cohesive  gold  filling  when  confined 
between  the  Avails  of  elastic  dentine  so  as  to  obtain  a  slightly 
greater  specific  gravity  than  the  cast  inlay.     However,  this  degree 


COHESIVE    GOLD    IN    THE    MAKING    OF    A    FILLING  125 

of  solidity  is  not  possible  of  attainment  unless  the  gold  is  eon- 
fined  and  the  Avedoing-  principle  is  taken  advantage  of. 

Cohesion  of  Gold.  The  surfaces  of  pure  gold  Avheii  absolutely 
clean  readily  cohere.  This  cohesion  is  brought  about  by  the  fric- 
tion of  the  surfaces  of  the  gold  when  in  absolute  adaptation.  The 
degree  of  cohesion  is  in  proportion  to  the  friction.  The  friction 
is  in  proportion  to  the  load,  the  extent  of  the  surfaces  in  opposi- 
tion and  the  speed  of  the  travel  of  the  surfaces  one  upon  the  other. 
Hence,  the  greater  the  load,  the  smaller  the  surface,  and  the  more 
rapid  the  movement  of  one  surface  upon  the  other  the  greater 
the  cohesion.  Polished  surfaces  of  gold  must  be  brought  into  co- 
adaptation  in  order  to  get  cohesion.  The  smaller  the  surfaces  and 
the  thinner  the  sheets,  the  less  load  and  speed  will  be  required. 

The  Serrated  Plugger  Points  are  used  in  condensing  cohesive 
gold  for  the  following  reasons:  That  these  polished  surfaces  may 
be  kept  small  and  uniform ;  that  great  pressure  (load)  may  be  eas- 
ily exerted  on  the  polished  planes  previously  left  in  the  surface 
of  the  gold  by  the  wedge-shaped  serrations.  The  mallet  is  applied 
to  give  the  additional  factor  in  friction  (speed)  as  the  fresh  gold 
is  moved  over  these  small  polished  surfaces.  The  above  conditions 
are  obtained  with  the  least  exertion  on  the  part  of  the  operator 
and  annoyance  to  the  patient  by  the  serrated  plugger  point,  which 
is  made  of  a  collection  of  pyramids  which  act  as  so  many  wedges 
and  exert  great  lateral  force  (load)  upon  the  polished  sides  of 
their  previous  impression.  That  gold  coheres  to  polished  surfaces 
can  be  easily  demonstrated  by  taking  any  cohesive  gold  filling 
and  burnishing  its  surface  to  a  glossy  finish.  Pellets  of  gold  from 
the  annealer  will  readily  cohere  and  the  filling  may  be  continued 
to  full  contour  by  applying  a  steel  burnisher  with  heavy  pressure 
drawn  over  the  surface  of  the  fresh  gold.  This  process  proves  that 
burnished  gold  coheres,  but  it  is  slow  and  la])orious  and  ol^jeetion- 
able  to  the  patient,  heuce  the  serrated  ])luggei'  point  which  ac- 
complishes the  same  result,  the  friction  of  polished  surfaces  of 
gold  under  pressure,  causing  their  welding. 

Bridging  is  the  tei-m  applied  to  that  faulty  manipulation  Avhich 
results  in  air  s])aces  within  the  body  of  the  filling,  caused  by  the 
gold  failing  to  reach  the  b(>ttom  of  the  indentations  of  the  serrated 
plugger  point. 

The  Cause  may  ])e  insufficient  pi-essure  being  given  the  plugger 
point,  lln-  ii-old  thereby  sto])j)iiig  short  of  the  bottom  of  the  serra- 
tions, or  it  may  be  caused  by  too  mucli  liglit  niallc)  iiig,  going  over 
tlie    <!()](]    surface    rcpcalcdly    llicrcbs'    bending   down    the    crests    of 


126  OPERATIVE   DENTISTRY 

the  pyramids  thus  choking  them  to  the  entrance  of  the  gold. 
Again,  it  may  be  caused  by  changing  to  a  plugger  with  a  less  num- 
ber of  serrations  to  the  millimeter,  or  one  wherein  the  serrations 
are  not  as  deeply  cut,  resulting  in  a  collection  of  pyramids  that  do 
not  reach  the  bottom  of  the  indentations  made  by  the  previous 
plugger. 

Plugger  Points  Should  Have  the  Same  Sized  Serrations.  Each 
operator  should  have  a  set  of  gold  plugger  points  same  denomina- 
tion as  to  the  cuttings  on  the  working  point  to  use  in  the  same  fill- 
ing. When  forced  to  change  to  one  of  different  sized  serrations  the 
surface  of  the  filling  should  be  gone  entirely  over  Avith  the  new  plug- 
ger to  be  used,  before  adding  additional  gold.  This  will  create  a  new 
set  of  facets  to  accommodate  the  gold  added  with  the  new  instru- 
ment.   (See  Figs.  176A  and  17GB.) 

A  little  care  in  this  respect  will  greatly  increase  the  specific  grav- 
ity of  the  cohesive  gold  filling. 

Rotating-  the  Plugger  in  the  Fingers  Should  Be  Avoided.  The  ser- 
rations are  cut  on  the  square  and  unless  the  point  is  rotated  one- 
foui'th  of  a  circle  each  time  the  pyramids  will  ride  the  crests  of  the 
indentations,  whereas  if  the  shaft  is  held  in  one  position  as  described, 
the  leverage  produced  by  the  plane  on  the  surface  of  the  plugger 
point  coming  in  contact  Avith  the  plane  on  the  surface  of  the  filling, 
will  twist  the  plugger  point  to  position  with  each  blow  of  the  mallet. 
All  this  will  prove  plain  to  tlie  vision  if  the  field  of  operation  is 
viewed  under  a  high  power  lens  while  operating  with  a  serrated 
plugger  on  the  surface  of  gold  in  a  technic  block. 

The  Size  of  the  Plugger  Point.  This  depends  entirely  upon  the 
force  with  which  it  can  be  used.  It  would  seem  from  all  the  facts 
at  hand  that  a  point  with  the  surface  of  one  square  millimeter  should 
be  regarded  as  the  maximum.  The  force  required  to  properly  con- 
dense gold  with  a  point  of  greater  surface,  is  either  not  permissible 
in  many  cases  or  often  not  possible  with  the  operator.  A  point  of 
one  square  millimeter  should  receive  a  load  of  15  pounds  pressure  at 
each  contacting  of  the  point. 

At  the  same  time  points  of  much  less  than  one-half  millimeter 
will  chop  the  sui-face  by  disturbing  the  gold  close  to  the  point  with 
each  impact ;  hence  we  are  limited  to  a  narrow  range  as  to  size  of 
points. 

Preparation  of  the  Foil.  The  gold  foil  may  be  used  from  the 
book  as  it  comes  from  the  dealer,  and  shaped  as  desired  by  the  oper- 
ator, or  it  may  be  purchased  as  cylinders,  squares,  ropes  and  various 
other  forms. 


COHESIVE    COLD    IX    THE    MAKING    OF    A    FILL1N(;  127 

The  shapiuy  sliould  ])e  done  Avithout  bringing  the  yold  in  direct 
contact  ^vith  the  fingers,  and  all  mani[)n]ation  and  catting  should  be 
done  ])revioiis  to  annealing. 

The  Application  of  the  Foil.  In  wliiehever  fonn  the  foil  has  been 
shajied,  it  should  be  so  placed  upon  the  surface  of  condensed  gold 
that  the  leaves  lay  Hat.  If  the  i)ellets  are  placed  so  that  the  leaves 
of  gold  are  crumpled  in  i)acking  to  ])lace  the  sjiecitic  gravity  will 
not  be  as  great  in  the  finished  filling.  Neither  will  the  cohesion  be 
as  perfect. 

Sheet  gold  has  left  in  it  a  certain  amount  of  si)ring  even  after  an- 
nealing that  has  to  be  overcome  if  folded.  The  less  handling  of  the 
sheets  in  folds  when  i)acking  tlic  better  the  result.  The  gold  should 
be  grasi)ed  by  the  carriers  Avith  as  small  a  bite  as  i)ossiljle  to  prevent 
])recondensation  and  carried  to  the  position  desired  and  condensed, 
with  no  attempt  to  shift  its  position  In-  pushing  or  poking  it  around 
over  the  surface. 

If  the  pellet  is  i)laced  near  a  wall,  it  should  be  placed  so  that  it 
lies  fully  against  that  wall  that  it  may  ])c  crowded  for  room  when 
condensed.  Short  of  this  will  hinder  the  wedging  principle  in  pack- 
ing. If  the  new  pellet  is  to  come  out  to  contour  it  should  reach 
slightly  beyond  contour  and  be  burnished  back  to  contour  with  a 
flat-faced  steel  burnisher. 

The  Forces  Used  in  Condensing-  Cohesive  Gold.  Time  are  two 
])]-ineipal  foi'ces  used  in  eondensinti-  cohesive  gold,  hand  ]))'essure  and 
blows  fi'om  the  mallet.  These  may  be  cither  alone  or  one  following 
the  other  or  in  combination:  the  last  named  is  the  most  popular,  the 
least  taxing  on  ])atient  and  opei'atoi-  and  produces  as  great  speeifie 
gravity  in  less  time.  However,  the  best  j-esults  ai'c  obtained  by  us- 
ing each  met  hod  at  given  times  in  the  i)rocess  of  building  most  fillings. 

To  Illustrate.  Hand  pressui-e  alone  should  be  used  in  the  filling 
of  convenience  angles.  Also  \\iien  on  account  of  ])()sition  tlu'  force 
must  be  a])i)]ie(|  a1  neai'ly  a  i-ight  angle  to  the  wall  against  which 
the  gold  is  beiiiK  condensed,  as  in  starting  a  filling  and  when  cover- 
ing the  seat  of  the  cavily  wifh  flic  firsf  one-half  millimetei'  of  gold. 

With  the  plugger  point  jxiinling  dii'cctly  at  a  dentinal  wall,  with 
a  thin  layer  of  gold  between,  the  elasticity  of  the  dentine  causes  the; 
gold  to  i-ebound  when  struck  a  blow  witii  the  mallet.  In  such  posi- 
tions th(!  closest  adaptation  is  secured  by  hand  pressui-e  alone  which 
should  be  app]ic<l  wifli  a  roi-kinu'  motion  secured  by  swaying  the 
outer  end  of  the  |.luL!iicr  from  side  to  side  for  a  distance  of,  say  one 
inch,  at  r-jich  change  of  position. 

Hand  Pressure  Alone  is  also  of  most  service  when  i)acking  gold 


128  OPERATIVE   DENTISTRY 

against  thin  walls.  Again  in  cases  where  the  condensing  force  should 
be  applied  at  an  angle  to  the  long  axis  of  the  shaft  of  the  plugger 
point  as  sometimes  met  with  in  distal  cavities  in  posterior  teeth  with 
a  distal  inclination.  Hand  pressure  alone  is  required  when  it  be- 
comes necessary  to  use  force  at  an  angle  which  would  tend  to  unseat 
the  filling. 

A  filling  should  never  receive  a  blow  through  the  plugging  instru- 
ment when  that  instrument  does  not  point  ciuite  directly  toward 
one  of  the  inner  walls  of  the  cavity,  preferably  the  seat. 

Mallet  Force  Alone  is  of  service  in  adding  the  last  portions  of 
gold  to  an  occlusal  surface  when  adding  thin  layers  of  gold  at  each 
time,  resulting  in  a  very  hard  surface. 

A  Good  Rule  is  to  increase  the  hand  pressure  (load)  both  in  fre- 
quency and  weight  as  you  increase  the  thickness  of  the  pellets  ap- 
plied, and  as  the  angle  at  which  the  gold  is  driven  to  a  dentinal  wall 
approaches  a  right  angle. 

The  Different  Plans  of  Mallet  Force. 

Hand  Mallet.  By  far  the  best  mallet  force  is  the  hand  mallet 
driven  by  an  experienced  assistant.  By  this  method  the  operator  is 
able  to  vary  the  amount  of  hand  pressure  (load)  and  its  relation  to 
the  mallet  force  (velocity)  at  will  all  through  the  filling,  as  well  as 
at  different  points  in  the  condensing  of  a  single  pellet  of  gold,  a  point 
of  no  small  consequence. 

The  Automatic  Mallet.  It  has  been  attempted  to  imitate  this 
combination  method  in  the  automatic  plugger,  and  is  today  the  best 
substitute  for  the  hand  pressure  and  assistant  mallet  method,  but 
it  must  be  regarded  as  a  substitute  only  and  supplies  a  need  in  the 
absence  of  better  facilities. 

Power  Mallet.  Power  mallets  either  electric  or  mechanically 
driven  by  the  engine  are  of  service  in  that  part  of  each  filling  where 
mallet  force  alone  is  indicated  as  previously  described.  But  this 
is  such  a  small  proportion  of  each  filling  that  most  operators  do  not 
care  to  bother  with  them  and  few  have  them  at  hand. 


CHAPTER  XXI. 

MANIPULATION  OF  COHESIVE  GOLD  IN  THE  MAKING  OF 
FILLINGS  BY  CLASSES. 

Class  One.    Pit  and  Fissure. 

This  class  of  cavities  is  the  easiest  of  all  in  that  they  are  sur- 
rounded by  solid  walls  of  dentine  with  generally  only  one  wall  miss- 
ing, which  is  the  means  of  access  to  the  cavity. 

Starting  the  Filling.  In  the  case  of  a  small  pit  cavity  it  is  gen- 
erally well  to  start  with  a  piece  of  gold  that  is  sufficiently  large  to 
more  than  cover  the  internal  wall  and  condense  the  greater  portion 
Avith  a  rather  large  plugger  point  using  hand  pressure  alone  on  this 
piece.  AVith  occlusal  cavities  the  inner  wall  is  the  pulpal  wall. 
"When  the  cavity  is  in  an  axial  surface  it  is  the  axial  wall. 

A  second  pellet  of  gold  may  be  added  and  condensed  in  the  same 
way.  The  mallet  force  should  now  be  used  on  a  smaller  plugger 
point  going  entirelj^  around  the  cavity  close  to  the  walls  holding  the 
shaft  of  the  plugger  at  an  angle  of  about  12  degrees  centigrade  to 
the  wall  against  which  the  condensing  is  being  done. 

In  Occlusal  Cavities  the  condensing  should  be  in  the  central  por- 
tion first :  then  next  to  the  distal  wall ;  then  along  the  buccal  and 
lingual  walls  and  lastly  the  mesial  wall.  This  plan  of  procedure 
pertains  to  each  separate  layer  of  gold  as  it  is  applied  when  treat- 
ing simple  occlusal  pits. 

In  Buccal  Cavities  the  order  of  stepping  is :  first,  center ;  second, 
ginuival:  tliii'd,  distal:  fourth,  mesial:  fifth,  occlusal. 

When  the  Cavity  Has  a  Long  Irregular  Outline  caused  by  the 
following  out  of  one  or  more  rather  long  fissures  the  plan  is  the  same, 
except  that  the  most  distant  arm  of  the  cavity  is  filled  first,  allow- 
ing the  gold  to  gradually  build  tOAvard  the  operator's  viewpoint, 
covering  the  base  wall,  portion  by  portion,  with  the  plugger  point 
always  at  the  given  angle  to  this  base  wall,  which  permits  of  the 
u.se  of  mallet  force  after  the  first  pieces  of  gold  have  been  securely 
anchored  along  the  disto-pulpal  line  angle. 

Class  Two.     Proximal  Cavities  in  Bicuspids  and  Molars. 

Beginning  the  Filling.  There  are  lln-ee  distinct  inelliods  of  slai-t- 
ing  a  filling  of  cohesive  gold  in  this  cla.ss  of  cavities.  It  is  well  if 
both  i;ingival  point  antjlos  are  sharfX'iied  to  a  convenience  angle.     It 

1  L'!» 


130 


OPERATIVE   DENTISTRY 


will  not  suffice  to  have  these  made  into  the  form  of  a  round  hole  or 
slot,  but  they  should  be  shaped  up  to  the  distinct  wedge  shape.  This 
shape  will  cause  the  condensed  gold  to  crowd  the  elastic  dentine  on 
all  sides  as  it  is  driven  to  place  and  insure  the  stability  of  the  first 
piece  of  gold.  If  this  small  convenience  angle  is  not  sharp  at  its 
deepest  point,  but  has  a  flat  wall  or  seat,  the  mallet  force  is  pre- 
cluded as  that  flat  wall  will  not  permit  its  use,  the  elasticity  of  which 
will  cause  the  gold  to  rebound  when  struck  a  blow,  whereas  when 
this  point  is  sharp  and  the  approaching  sides  leave  a  wedge-shaped 
opening  the  gold  is  firmly  grasped  when  driven  to  position.  Atten- 
tion to  this  small  detail  wnll  make  easy  starting  of  such  fillings. 
As  to  the  Three  Plans  of  Starting  Class  Two. — The  First  Plan, 


Fig.    74. — Starting  cohesive  gold,   first  plan. 


and  probably  the  most  popular,  is  to  fill  one  convenience  angle,  the 
one  the  farthest  from  the  viewpoint  of  the  operator,  and  while  sup- 
porting this  in  position  with  a  suitable  instrument  Iniild  along  the 
gingivo-axial  line  angle  to  the  other  point  angle. 

A  Second  Plan  is  to  fill  each  point  angle  separately  and  join  the 
two  with  a  third  piece  of  gold  laid  along  the  gingivo-axial  line  angle. 

A  TJiird  Plan  is  to  start  with  a  quantity  of  gold  sufficient  to  fill 
both  point  angles  and  cover  the  connecting  line  angle  as  well  as  a 
considerable  portion  of  the  gingival  wall  next  to  the  axial.  This  last 
plan  is  one  used  by  some  experienced  operators  and  is  well  to  be  at- 
tempted when  working  for  speed.  The  beginner  Avill  do  well  with 
the  first  plan. 

The  Order  of  Stepping  the  Plugger  in  Class  Two.     With  each 


COHESIVE    GOLD    IX    THE    MAKING    OF    FILLINGS    BY    CLASSES 


131 


pellet  of  gold  iicldcd.  the  wedging  principle  is  made  most  effective 
by  the  following  order  of  stepping :  Center  of  filling  first ;  contour 
second ;  ascending  line  angles  third ;  surrounding  walls  fourth  and 
against  ascending  cavo-surface  angles  fifth,  keeping  the  long  axis 
of  the  plugger  shaft  at  about  a  twelve  degree  centrigrade  angle  to 
the  axial,  buccal  and  lingual  walls. 

When  the  Gold  Extends  Beyond  Contour  it  should  l)e  I)unnshed 
back  to  correct  position  and  the  plugger  again  stepped  along  the 
contour,  holding  the  plugger  close  to  a  line  of  the  long  axis  of  the 
tooth,  instead  of  striking  the  gold  at  nearly  a  right  angle  to  this  line, 
a  practice  so  common  with  operators,  and  one  that  has  a  tendency  to 
unseat  the  filling  and  separate  the  layers  of  the  filling  already  con- 
densed. 

The  Progress  of  the  Filling  should  be  kept  on  a  plane  parallel 


Fig.    75. — Starting;   cohesive   gold,   seton<i    iilan. 

to  the  ])laiie  of  the  gingival  wall  and  kept  in  this  plane  to  near  the 
completion  of  the  filling,  having  a  strict  care  as  to  complete  contour 
in  the  proximal,  as  the  filling  advances. 

Covering  the  Pulpal  Wall.  There  ai-e  two  plans  of  coverina'  the 
step  i)oi'tion  in  Class  Two.  The  First  Finn.  The  fii'st  and  most 
common  is  to  build  the  cavity  poi'tion  to  a  level  of  the  ])uli)al  wall 
and  gradually  cover  the  pulpal  wall  ])y  allowing  each  pellet  of  gold 
to  extend  a  little  farther  than  the  pi'evious  one  out  over  the  ])uli)al 
wall  till  llic  pulpal   point  angles  have  been  reached. 

Th(  S((:o)i(l  Flan  is  to  stai't  an  indcfx-ndcnt  body  of  gold  in  the 
pulfjal  i)oint  angles,  in  one  of  the  three  ways  outlined  in  starting  the 
cavity  portion  on  the  <rinj,'-ival  wall  and  finally  uniting'  tlie  two  por- 
tions of  tlie  fillinjr.     Wliicliever  plan   is  used  nothing  should  be  done 


132 


OPERATIVE    DENTISTRY 


in  the  way  of  covering  the  pulpal  wall  till  the  gold  in  the  cavity  por- 
tion has  reached  a  level  with  the  axio-pnlpal  line  angle. 

The  Contact  Point.  The  building  of  contact  point  should  receive 
special  attention  when  the  proper  height  of  the  filling  has  been 
reached.  The  gold  should  be  thoroughly  condensed  against  the  prox- 
imating  tooth  much  in  the  same  manner  as  it  is  wedged  against  the 
walls,  and  should  receive  extra  malleting  to  insure  extreme  hard- 
ness. 

Position  of  Contact  Point.  When  the  proximating  tooth  is  in- 
tact, the  contact  point  should  be  in  about  the  same  position  as  it 
was  previous  to  decay,  and  should  be  a  contacting  point  and  not  sur- 
face or  a  line  of  contact.     This  should  round  away  from  this  point 


Fig.   76. — Starting  cohesive  gold,  third  plan. 

in  much  the  same  manner  as  do  the  surfaces  of  two  marbles  when 
touching,  and  has  come  to  be  spoken  of  as  the  "marble  contact." 
(See  Fig.  26.) 

Moving-  Contact  Point  Flush  to  Occlusal.  The  contact  point 
should  be  moved  occlusally  when  both  promixating  surfaces  are  to 
be  restored,  one  a  mesial  and  the  other  a  distal  filling  in  the  teeth 
making  up  the  proximal  space  being  considered,  and  when  there  has 
been  considerable  occlusal  wear.  This  will  result  in  a  contact  point 
from  which  the  surfaces  round  away  in  all  directions  except  toward 
the  occlusal  surface  and  is  known  as  the  "half  marble  contact"  ad- 
vised for  the  above  condition  only.  In  this  connection  attention  is 
called  to  the  immunity  to  decay  of  proximating  surfaces  where  the 
"half  marble  contact"  has  been  produced  by  occlusal  wear.  Many 
instances  are  seen  where  caries  already  started  in  such  spaces  have 


COHESIVE    GOLD    IX    THE    MAKING    OF    FILLIXGS    BY    CLASSES 


133 


ceased  to  progress  because  of  the  cleanliness  of  such  surfaces,  due 
to  the  lack  of  the  egress  of  food  substances. 

The  Last  Portions  of  Gold.  After  leaving  contact  point  the  last 
portions  of  gold  are  added  to  restore  normal  contour  or  as  near  that 
condition  as  occlusion  and  articulation  will  permit  giving  special 
care  to  complete  covering  of  the  cavo-sui'face  angle  at  all  points. 

Filling-  Class  Two  With  Matrix  in  Position.  This  may  ])e  done, 
and  is  advised  by  some  operators,  who  advance  the  theory  of  addi- 
tional condensation  due  to  the  presence  of  the  substitute  for  the 
missing  wall. 

"When  the  matrix  is  used  it  should  not  be  adjusted  till  the  gin- 
gival cavo-surface  angle  is  covered.     It  should  be  thoroughly  wedged 


Fig.  77.— Burnishijig  back  excess  gold  foil  in  covering  the  gingival   margin. 

at  the  gingival.     The  matrix  should  be  removed  just  before  the  gold 
has  l)ecn  built  to  the  height  of  contact  point. 

The  Use  of  the  Separator  in  Class  Two.  In  cases  ^^here  prelim- 
inary separation  has  not  been  made,  a  mechanical  separation  should 
be  adjusted  and  tightened  at  shoi-t  intervals  to  the  full  extent  of 
safety.  This  will  j)e)'mit  of  better  and  more  thoi'ough  finishing  of 
contact  point  as  the  slight  space  resulting  will  be  taken  up,  upon 
the  removal  of  the  separator. 

Class  Three.    Proximal  in  the  Six  Anterior  Not  Involving  the  Angle. 

Starting  the  Gold,  in  cavities  class  three,  is  llie  same  in  hu-ge  or 
small  cavities,  'i'he  gold  is  first  condensed  into  the  wedge-shaped 
convenience  angle  farthest  from  the  viewpoint  of  the  operator  which 
is  the  gingivo-axio-lingual  angle.     The  gold  is  ke|)t  in  Ibis  triangular 


134 


OPERATIVE   DENTISTRY 


form  by  covering  equally  rapidly  the  three  walls  forming  the  angle ; 
the  gingival,  axial  and  lingual  walls,  keeping  the  shaft  of  the  plug- 
ger  pointing  all  the  time  at  the  point  angle  primarily  covered. 
When  the  gold  has  been  built  out  along  the  gingivo-lingual  line 


Fig.   78. — Covering  the  gingivo-lingual  angle  with  cohesive  gold. 


angle  to  the  cavo-surface  angle  great  care  must  be  taken  at  this  stage 
of  the  filling  that  the  linguo- gingival  angle  is  covered  and  the  gold 
built  to  full  contour,  as  this  is  the  only  time  it  can  be  correetlj^  done 
with  the  force  directed  in  the  right  direction.     As  the  gold  reaches 


COHESIVE    GOLD    IX    THE    MAKING    OF    FILLINGS    BY    CLASSES  135 

the  lieight  of  the  gingivo-axio-labial  angle  this  should  be  thoroughly 
filled  and  the  filling  continued,  maintaining  the  same  level  of  the 
gold,  restoring  full  contour  past  contact  point  which  should  be  well 
condensed  and  burnished. 

Filling  Incisal  Angie.  Shortly  after  passing  contact  point  the 
gold  should  be  advanced  along  the  axiodingual  angle  to  the  incisal 
angle  which  should  then  be  filled  using  hand  pressure  alone  as  the 
direction  of  the  force  will  not  permit  of  the  use  of  the  mallet.  The 
filling  should  then  be  completed  with  the  plugger  point  still  directed 
toAvard  the  angle  where  gold  was  first  condensed,  the  last  portions 
of  gold  being  added  to  the  labial  portion  of  the  filling  at  the  incisal 
extremity. 

With  Ling'ual  Approach  in  Class  Three  the  whole  plan  is  re- 
versed. The  gold  is  first  built  into  the  gingivo-axio-lalnal  angle. 
The  plugger  point  is  maintained  in  a  position  pointing  at  this  angle 
as  the  filling  progresses,  till  the  last  additions  of  gold  are  to  the 
lingual  surface  at  the  incisal  extremity,  all  the  Avhilc  the  operator  is 
woi'king  ti»  the  image  reflected  in  the  mouth  mirror. 

The  Lingual  Approach  Is  Advised  in  cases  vrhere  ani])le  pi-elim- 
inary  separation  is  secured  or  when  the  lingual  wall  is  Avanting  and 
the  axial  wall  meets  the  lingual  cavo-surface  angle.  That  said  about 
the  use  of  the  mechanical  mallet  in  Class  Two  applies  to  Class 
Three  with  equal  force. 

Class  Four.     Proximal  Cavities  in  Incisors  and  Cuspids  Involving' 

the  Angle. 

The  removal  of  the  incisal  angle  i)crmits  of  the  ])lugger  point  be- 
ing used  in  an  ideal  angle  to  the  Avails  and  allows  the  force  being 
applied  more  nearly  fi-om  the  direction  that  the  sul)sequcnt  force  of 
sei'vice  is  I'occivcd. 

Starting-  the  Filling-.  These  fillings  are  stai-ted  as  has  just  been 
descrilHMi  with  Class  Three;  howevei'.  the  gingival  wall  should  be 
most  i-apidly  covered  and  the  ])lan  of  building  similar  to  that  de- 
scribed fur  Class  Two,  keeping  the  surface  of  the  gold  ])arallel  to 
the  jdanc  of  the  gingi\al  wall,  restoi'iiig  lost  contour  as  the  filling 
advances,  and  maintaining  the  ])lugg('i'  ])()iiit  at  al)out  12  degrees 
centigivule  to  the  surrounding  walls. 

The  Final  Portions  of  Gold  slionld  he  ('i)n<l('ns('(l  on  llic  cxirenie 
incisal  ant^le  witji  the  shaft  of  the  i)lugg<>r  ])oint  still  niaiiilained  at 
an  angle  (»f  12  degrees  1o  the  plane  of  the  axial  Avail. 

The  Layers  of  Gold  in  Class  l-'onr  should  i-cceive  some  atlcnlion 
and    what   is  said    in   this  (•oniic<-1ion   is  Irnc   of  all   conloui-   resffira- 


136  OPERATIVE   DENTISTRY 

tions  subject  to  great  stress.  Not  a  little  trouble  has  been  experi- 
enced in  the  breaking  of  such  fillings  through  given  lines  of  fracture. 
These  should  be  noticed  and  the  layers  of  gold  leaf  so  placed  as 
to  cross  these  lines.  The  tensile  strength  of  the  sheets  of  gold  is 
greater  than  the  usual  cohesion  obtained  giving  a  filling  more  strength 
across  the  laminations  than  parallel  with  them. 

Class  Five  Cavities  in  the  Gingival  Third. 

Class  Five  cavities  in  the  gingival  third  need  no  special  mention 
as  they  are  built  under  the  rules  already  outlined  in  Class  One. 

The  gold  is  usually  started  in  the  disto-axio-gingival  angle  and 
carried  along  the  gingivo-axial  line  angle  to  the  other  gingival  point 
angle.  The  gingival  wall  will  be  the  first  wall  to  be  completely  cov- 
ered. The  mallet  force  should  not  be  directed  at  a  right  angle  until 
that  wall  has  been  covered  with  a  considerable  layer  of  gold. 

Class  Six.    Abraded  Surfaces. 

These  cavities  are  built  the  same  as  large  flat  cavities  in  the  same 
surface,  the  principles  of  which  have  been  given. 


CHAPTER  XXII. 
FINISHING  GOLD  FILLINGS. 

Secondary  Consideration.  When  a  gold  filling  has  been  built  to 
its  full  size,  the  entire  surface  should  be  gone  over  with  a  plugger 
point  of  moderate  size.  The  point  should  be  stepped  so  as  to  cover 
every  accessible  part  of  the  filling. 

A  light  mallet  with  a  hard  surface  should  be  used.  A  two  ounce 
steel-faced  mallet  is  preferred. 

Burnishing-.  All  accessible  parts  of  the  surface  should  then  be 
thoroughly  burnished  with  a  steel  burnisher.  The  egg-shaped  bur- 
nisher is  of  most  universal  use  as  it  will  reach  most  positions. 

If  the  filling  is  a  proximal  filling  of  Classes  Two,  Three  or  Four, 
a  thin  steel  hand  matrix  should  ])e  forced  between  the  filling  and  the 
proximating  tooth  to  burnish  the  contact  point  and  to  better  con- 
dense and  harden  the  filling  at  this  place.  This  is  done  by  swinging 
the  handle  back  and  forth  describing  the  part  of  a  circle,  till  there 
is  moi'e  or  less  freedom  of  movement  of  the  burnisher. 

Following  This  Secondary  Condensation  the  process  of  smoothing 
the  surface  with  abrasives  begins.  The  first  efforts  should  be  to  find 
cavity  outline,  second,  to  correct  contour  in  localities  where  an  ex- 
cess ha>s  been  built  and  third,  to  polish  the  contact  point. 

This  is  best  accomplished  by  the  use  of  small  carljorundum  stones 
on  occlusal  surfaces,  disks  on  buccal,  lingual  and  labial  contours, 
and  narrow  coarse  strips  in  the  proximal,  gingivally  from  contact 
point  assisted  by  the  use  of  file  cut  burnishers. 

Attention  should  first  be  given  to  all  parts  of  the  filling  except 
contact  point  which,  in  all  proximal  fillings  should  be  the  last  place 
to  receive  finish. 

The  Use  of  the  Saw  in  the  proximal  space  in  the  finishing  of  the 
filling  cannot  be  ttjo  .strongly  condemned.  In  the  first  place  no  cut- 
ting in.strument,  or  coarse  abradent,  as  strips  or  disks,  should  Ijc 
made  to  pass  contact  point  except  whei'c  there  has  been  ample  })re- 
liminary  separation  and  the  return  of  the  teeth  to  position  is  relied 
upon  to  close  the  resultant  space.  Again  there  is  no  excuse  for  build- 
ing an  excess  of  contour  sufficient  to  engage  the  bite  of  a  saw  blade. 

The  Excess  at  the  Gingival  should  be  sliglit,  and  it,  with  the  ex- 
cess fullness  ill  11h'  ciiihrasurcs,  should  be  filed  away  with  the  files, 
or  whittled  off  with  the  burnishing  knife,  the  edge  of  which  should  be 
keen.     The  files  should  ])e  cai'ried  through  the  eiii1)t'asures  as  fai"  to- 

y.'.T 


138  OPERATIVE    DENTISTRY 

ward  the  center  of  the  filling  as  possible  and  drawn  directly  outward 
and  over  the  edge  of  the  filling  out  to  the  external  enamel  surface. 

The  Finishing"  Knife  should  be  engaged  into  the  substance  of  the 
gold  and  drawn  from  the  gum  and  at  the  same  time  outward,  tak- 
ing off  only  a  small  portion  of  gold  at  each  cut. 

Coarse  Abrasives,  as  carborundum  stones  and  coarse  disks  and 
strips,  should  be  abandoned  as  soon  as  a  near  approach  to  the  cavo- 
surface  angle  is  reached,  and  the  files,  plug-finishing  burs,  and  knife 
edged  instruments  resorted  to,  to  bring  into  view  the  exact  cavity 
outline,  after  which  the  finer  strips  and  disks  should  be  employed  to 
bring  gold  and  tooth  substance  to  an  exact  level  at  the  cavo-sarface 
angle  for  the  entire  cavity  outline. 

Finishing  Strips  in  the  Proximal.  To  reduce  the  quantity  of  gold 
from  contact  point  to  the  gingival,  a  coarse  finishing  strip  sufficient- 
ly narrow  to  reach  from  the  gingival  outline  to  near  the  contact 
point  only,  is  of  advantage.  This  strip  is  introduced  by  sharpening 
one  end  and  passing  through  the  embrasure  below  contact  point  and 
then  drawn  back  and  forth  till  the  desired  surface  is  secured. 

Fine  narrow  linen  strips  are  then  used  in  the  same  way  to  give 
a  final  finish  to  this  place  of  difficult  access. 

When  the  Entire  Cavity  Outline  Has  Been  Exposed  and  the  sur- 
face otherAvise  made  ready  for  the  final  finish  the  separator  should 
be  tightened  another  degree,  when  it  will  be  found  that  a  broad  fine 
linen  strip  will  easily  pass  contact  point.  This  should  be  given  three 
or  four  sweeps  with  this  broad  strip  not  too  tightly  drawn,  when 
the  contact  point  should  be  considered  finished. 

The  separator  should  be  gradually  loosened  and  removed,  the  rub- 
ber dam  removed  and  the  filling  tested  for  occlusion  and  articula- 
tion and  properly  shaped.  The  filling  should  then  receive  a  thorough 
finish,  with  wood  points,  leather  wheels  and  tooth  cleaning  brushes, 
carrying  first  pumice,  then  whiting,  till  the  surface  of  the  filling  is 
as  smooth  as  the  external  enamel  surface. 


CHAPTER  XXIII. 

MANIPULATION  OF  AMALGA:\I  IN  THE  MAKING  OF  A 

FILLING. 

Definition.  Anuilgam  is  a  coiuposition  of  inercury  witli  one  or 
more  other  metals.  It  is  most  commonly  combined  with  two  or  more 
other  metals  which  have  been  previously  alloyed  and  finely  divided 
either  as  shavings  or  filings  to  facilitate  union  wdth  the  mercury. 

History.  Amalgam  for  the  filling  of  teeth  was  int?-odnced  into 
Fi-ance  about  the  year  182G  by  M.  Teveau,  who  called  it  "silver 
paste."  This  was  composed  of  silver  and  mercury  alone,  and  must 
have  given  very  unsatisfactory  results  as  compared  with  those  se- 
cured in  the  use  of  our  modern  alloys. 

Reception.  The  use  of  amalgam  A\as  given  a  most  uu^velc()lne 
reception  l^y  the  profession  at  large,  while  the  converts  of  the  "new 
process"  were  equally  emphatic  in  their  praise  of  the  ucav  filling 
which  "would  certainly  cheapen  dentistry,  and  harm  the  profession." 
But  time  has  proved  amalgam  to  be  a  blessing  to  the  poorer  classes 
in  that  it  brings  dentistry  within  the  reach  of  all  purses  and  has 
thereby  proved  of  advantage  to  the  dental  profession  by  broadening 
its  field  of  usefulness. 

"While  amalgam  has  many  faults  and  should  generally  be  avoided 
when  finance  will  permit,  the  fact  still  remains  that  moi'c  teeth  have 
been  saved  through  its  use  than  with  any  other  filling  material. 

However  the  ])ercentage  of  salvage  is  greater  Avith  gold,  which 
foi'ces  amalsiam  to  second  place. 

The  Properties  of  Amalgam  wliidi  rcndei'  it  of  value  as  a  filling 
material  ai'c:  I'^ii'st.  its  ])lasticity  eliminating  access  form  in  cavity 
preparation,  making  ])ossil)le  the  1)uilding  up  of  lost  contours  in  inac- 
cessible places  in  the  mouth,  where  convenience  and  access  foi-ms  are 
hard  to  secui'e.  sufficient  foi*  the  manipulation  of  gold  either  co- 
hesive or  as  an  inlay;  second,  its  ])i'operty  of  being  but  slightly  af- 
fected by  the  oral  lluids,  and  tlic  fact  that  it  is  faii-ly  stable  as  to 
bulk  and  shaj)e;  and  last,  but  not  ](>ast  in  the  minds  of  many  pa- 
tients, we  ai-e  soi-ry  to  say,  is  its  cheapness,  as  most  dentists  see  fit 
to  l>uild  filliny:s  of  amalgam  for  a  much  smallei"  fee  than  gold. 

The  Objections  to  Amalgam  arc:  lis  tendency  to  discolor  both 
as  t(j  its  (xposcd  surface  and  Ihc  Iccth  with  which  it  has  l)een  filled 
due  to  slight  leakage  Avith  old  fillings;  its  comj)arative]y  large  ex- 
pansion and   contraction    range;   its  continued    flow   under   load;   its 


140  OPERATIVE    DENTISTRY 

poor  edge  strength;  its  spheroiding  during  setting,  when  not  prop- 
erly mixed  from  a  perfect  alloy.  It  is  also  liable  to  injury  between 
the  time  of  introduction  and  complete  setting  through  carelessness 
of  either  dentist  or  patient. 

The  Extent  of  Expansion  and  Contraction  of  amalgam  is  not  un- 
der the  control  of  manipulation  by  the  operator,  but  is  controlled 
by  the  composition  of  the  alloy  both  as  to  materials  used  and  their 
proportions;  as  well  as  the  method  of  their  preparation. 

The  Flow  of  Amalgam  under  pressure  is  the  term  applied  to  the 
tendency  of  amalgams  to  flatten  or  move  from  under  stress. 

Most  metals  will  yield  or  flatten  under  a  given  stress  in  proportion 
to  the  load,  up  to  a  given  point,  and  then  cease  unless  the  weight  is 
increased.  However  amalgam  continues  to  yield  as  long  as  the  pres- 
sure is  continued  even  though  it  is  not  increased. 

This  peculiarity  in  amalgam  explains  the  phenomenon  often  ob- 
served in  the  mouth.  Amalgams  differ  as  to  the  amount  of  force 
necessary  to  produce  flow,  yet  the  peculiarity  is  exhibited  by  all 
amalgams. 

Edge  Strength  in  a  Filling  is  the  term  applied  to  the  resistance 
a  filling  shows  to  stress  upon  thin  margins  at  that  portion  of  a  fill- 
ing which  covers  the  marginal  bevel. 

Edge  Strength  in  Amalgam.  This  depends  first,  upon  the  metals 
entering  into  the  alloy.  The  greater  the  proportion  of  silver  enter- 
ing into  the  amalgam  up  to  seventy-five  per  cent,  the  greater  the 
edge  strength.  Above  seventy-five  per  cent  it  becomes  more  brittle. 
Second,  the  manner  of  packing.  Third,  the  amount  of  actual  union 
between  mercury  and  alloy.     Fourth,  bulk  at  margin. 

The  Maximum  Strength  will  be  obtained  when  the  alloy  contains 
just  enough  mercury  so  that  the  mass  will  take  the  impression  of 
the  skin  markings  after  prolonged  kneading  between  the  thumb  and 
forefinger.     Any  more  or  less  weakens  the  edge  strength. 

The  Length  of  Time  the  Alloy  Stands  has  an  effect  upon  edge 
strength,  as  amalgams  made  from  alloys  lose  their  edge  strength  pro- 
gressively with  time,  the  more  rapidly  the  higher  the  average  tem- 
perature. 

However  Aged  Alloys  SJiow  Less  Variations  in  Expansion,  Con- 
traction and  Range,  and  artificial  aging  is  resorted  to  for  this  rea- 
son and  is  done  by  annealing.  This  annealing  produces  an  amalgam 
that  shows  more  uniform  and  consistent  properties. 

Annealing  of  Amalgam  is  accomplished  by  subjecting  the  alloy 
when  freshly  cut  to  either  a  dry  or  moist  heat  ranging  from  110°  F. 


AMALGAM   IX    THE    MAKING    OF    A   FILLING  141 

to  212°  F.  for  some  hours  or  days.  The  lower  temperature  for  a 
lonofer  period  produces  the  best  results. 

Effect  of  Annealing.  The  artificial  aging  increases  the  contrac- 
tion, the  flow,  and  the  ability  to  withstand  the  crushing  strain;  the 
amalgam  requires  less  mercury,  and  sets  slower. 

The  Alloy  Showing  the  Least  Expansion  and  Contraction  ^\  hen 
unannealed  is  composed  of  seventy-two  parts  silver  and  twenty- 
eight  parts  tin  and  may  be  modified  very  slightly  by  adding  a  small 
per  cent  of  copper  or  other  metals.  Wlien  annealed  the  above  for- 
mula of  silver  tin  alloy  should  be  changed  to  seventy-six  parts  sil- 
ver and  twenty-four  parts  tin,  to  get  a  stable  amalgam. 

Cavity  Preparation  for  Amalgam.  IMany  of  the  failures  in  the 
use  of  amalgam  attributed  to  the  property  of  the  material  used  are 
in  fact  due  to  laxity  in  cavity  preparation,  since  many  practitioners 
believe  that  thoroughness  is  unnecessary  in  this  particular.  The 
preparation  of  a  cavity  for  the  reception  of  amalgam  is  even  more 
exacting  than  for  gold,  as  the  operator  is  dealing  with  a  filling  ma- 
terial possessed  of  a  greater  number  of  faults,  each  of  which  must 
be  given  consideration,  and  the  cavity  should  be  prepared  in  such 
a  manner  as  to  minimize  these  to  the  least  degree.  In  compar- 
ing amalgam  Avith  gold  it  might  be  said  that  amalgam  requires 
less  access  in  awkward  localities  in  the  mouth,  requires  much 
separation  in  proximal  fillings,  and  that  the  outline  form  must  re- 
ceive more  careful  consideration  as  the  margins  must  be  farther 
removed  from  positions  of  great  liability  to  caries,  as  well  as  stress. 

Flat  Seats  for  Fillings  are  even  more  imperative  than  Avith  gold, 
and  the  occlusal  step  must  be  broader  l)ucco-lingually.  The  enamel 
walls  must  be  finished  Avith  as  great  care,  Avith  a  ca\''0-surface  angle 
more  acute,  and  a  more  deeply  buried  bevel  angle.  Cavities  must 
have  more  retentive  form. 

The  Rubber  Dam  is  very  essential  as  it  is  imperative  that  amal- 
gam Ijc  built  against  dry,  freshly  cut,  walls  and  margins.  It  is  as 
impossible  to  make  a  good  amalgam  filling  as  it  is  a  good  gold  fill- 
ing against  moist  Avails.  The  residue  from  the  saliva  upon  the  Avails 
will  shoAv  leakage  more  quickly  Avith  the  amalgam  filling  than  with 
the  gold.  When  operators  come  to  the  full  realization  of  this  fact 
and  manipulate  all  amalgam  filliugs  Avith  as  gi'cat  care  as  gold,  with 
reference  to  dry  conditions,  the  frequent  failures  of  amalgam  will 
be  materially  lessened. 

The  Matrix.  All  cavities  fillc*!  w  iiti  amalgam  must  have  coiiliii- 
uons  sun-ouiidiiig  walls.     This  will  necessitate  the  adjustment  of  the 


142  OPERATIVE    DENTISTRY 

matrix  in  cases  where  a  wall  is  missing  and  applies  to  all  Class  Two 
cavities  which  reach  the  occlusal  surface. 

The  matrix  should  be  thoroughly  wedged  at  the  gingival,  to  pre- 
vent excess  contour  at  this  point,  and  to  secure  additional  space  that 
contact  point  may  be  made  close.  It  should  be  made  of  steel  as  thin 
as  one  one-thousandth  of  an  inch.  It  should  be  made  to  encircle  the 
tooth  firmly  either  by  ligating  or  by  a  retaining  appliance,  several 
of  which  are  on  the  market.  When  two  proximal  fillings  are  to  be 
built  at  the  same  time  and  in  the  same  proximal  space,  two  matrices 
are  necessary,  one  for  each  tooth  involved. 

However,  better  results  are  obtained,  particularly  with  reference 
to  proper  contact  restoration,  by  building  up  and  finishing  one  fill- 
ing first,  and  then  building  the  other  filling  at  a  subsequent  sitting. 
By  using  a  specially  prepared  matrix  band  of  the  proper  size  for 
the  second  filling,  with  a  hole  cut  in  the  matrix  to  allow"  the  metal 
to  protrude  at  the  point  of  contact  w^ith  the  first  made  filling,  an 
ideal  result  may  be  obtained. 

Separation.  Preliminary  or  immediate  separation  is  just  as  es- 
sential in  the  use  of  amalgam  as  gold. 

Making-  the  Proper  Proportions  of  Alloy  and  Mercury.  Each 
operator  should  test  his  favorite  alloys  and  determine  the  exact 
amount  of  mercury  for  a  given  quantit}^  of  alloy,  and  b}^  the  use 
of  a  pair  of  balances  be  able  to  always  mix  in  exactly  the  same  pro- 
portions. By  this  means  the  operator  is  able  to  produce  the  best 
product  by  having  the  amalgam  at  its  best.  By  the  uniformity  he 
becomes  familiar  with  the  habits  of  that  particular  alloy. 

This  method  need  not  be  a  time-loser,  if  the  portions  of  alloy  and 
mercury  are  previously  put  up  in  separate  capsules  ready  for  im- 
mediate use.  In  early  practice  this  can  be  done  by  the  dentist  him- 
self at  leisure  times  and  in  after  years  by  the  assistant. 

Making  the  Mix.  Upon  the  thorough  incorporation  of  the  mer- 
cury with  the  alloy  prior  to  placing  in  the  cavity  depends  much  of 
the  good  qualities  of  an  amalgam  filling.  Poorly  mixed  alloys  have 
little  strength.  Amalgamation  in  an  amalgam  filling  is  never  entirely 
complete,  and  while  this  process  is  going  on,  there  is  a  certain 
amount  of  molecular  action,  which  tends  to  change  the  form  of  the 
filling  as  a  whole.  A  very  great  per  cent  of  this  union  may  be  in- 
duced before  placing  the  filling  by  a  thorough  preliminary  mixing 
and  kneading  of  the  mass. 

To  this  end  the  alloy  and  mercury  should  be  put  into  a  wedge- 
wood  mortar  and  thoroughly  ground  together  till  the  contents  seem 
to  have  become  one  mass.     It  should  then  be  removed  to  the  palm 


a:mal(;;am  ix  the  making  of  a  filling  143 

of  the  hand  and  made  into  a  pcllot  and  then  transferred  to  the  thumb 
finger  grasp  and  rolled  between  the  fingers  with  sufficient  force  to 
produce  a  decided  squeaking  noise,  sometimes  spoken  of  as  the  "cry 
of  tin.""  p]ither  too  little  or  too  much  mercury  will  destroy  this 
sound  which  should  l)e  sought.  This  kneading  should  be  continued 
till  the  maximum  plasticity  has  been  secured,  and  the  tendency  to 
stiffen  has  just  appeared. 

Wringing-  Out  Excess  Mercury.  All  surplus  mercury  should  be 
expressed  as  soon  as  detected.  With  small  masses  this  is  thoroughly 
and  quickly  done  l)y  grasping  the  mass  between  the  ball  of  the  thumb 
and  the  tip  of  the  first  or  second  finger.  The  flesh  of  the  fingers 
should  entirely  cover  the  mass  from  view.  Then  by  a  rocking  mo- 
tion in  which  the  mass  is  kept  entirely  covei'ed  the  mercury  svill 
appear  from  between  the  fingers  and  not  carry  Avith  it  any  appreci- 
able amount  of  the  alloy. 

If  the  mass  is  too  large  to  keep  entirely  covered  during  the  proc- 
ess, it  may  be  placed  in  a  chamois  skin  and  wrung  to  dryness,  or  di- 
vided into  pieces  sufficiently  small  to  be  manipulated  with  the  fingers. 
As  soon  as  the  excess  mercury  has  been  expressed  the  whole  mass 
should  be  again  kneaded,  as  it  should  not  be  allowed  to  stand  in  this 
compressed  condition.  The  mass  should  be  rolled  between  the  thumb 
and  finger  into  a  loose  rope,  In-oken  into  pieces,  and  laid  in  a  posi- 
tion convenient  to  cany  to  the  mouth.  The  rope  or  ball  of  amal- 
gam should  never  be  cut  with  instruments,  as  that  part  close  to  the 
instrument  is  compressed  and  rapid  setting  facilitated. 

Amalg-am  Pluggers.  The  packing  instruments  sliouid  l)e  as  large 
as  can  be  well  used  in  the  cavity,  that  the  whole  mass  may  receive 
the  force  of  compression  at  each  effort.  The  face  of  the  plugger 
should  be  serrated  to  prevent  slipping.  A  l)all  l)urnisher  should 
not  be  used  in  packing  amalgam,  but  is  intended  foi'  finishing  after 
the  amalgam  has  set. 

Making-  the  Filling-.  Tlie  cavity  should  be  in  complete  readiness 
to  receive  the  amalgam  immediately  after  it  has  l)een  prepared.  The 
size  of  the  portions  will  depend  upon  the  orifice  of  the  cavity,  and 
should  be  as  large  as  can  be  easily  crowded  into  the  opening.  This 
should  be  immediately  compressed  upon  the  seat  of  the  cavity  with 
as  large  a  jduggei-  as  possible,  with  a  rocking  motion  and  as  much 
•weight  as  the  circumstances  will  permit.  When  using  a  point  that 
is  much  smaller  than  the  cavity,  the  same  Avedging  principle  used  in 
packing  gold  should  be  employed;  that  is,  compi-ess  the  central  por- 
tion of  the  mass  first  and  against  the  walls  last.  A  burnisher  should 
not  be  used  ;  neithei-  should  the  bui'iiishing  nor  \\i|)iiig  motion  be  used. 


144  OPERATIVE   DENTISTRY 

but  all  compressing  force  should  be  directed  at  a  right  angle  to  the 
base  wall. 

Quite  a  body  of  excess  should  then  be  added  to  the  occlusal  por- 
tion and  a  plugger  point  applied  with  mallet  force  which  should  be 
augmented  with  hard  hand  pressure.  The  hand  pressure  and  mallet 
force  combined  will  produce  a  more  dense  filling  than  by  any  other 
method  and  at  the  same  time  crowd  the  yet  movable  particles  of  amal- 
gam and  alloy  into  closer  adaptation  to  every  portion  of  the  cav- 
ity walls. 

Trimming'  Amalgam  Fillings.  After  packing  the  amalgam  it 
should  be  allowed  to  set  undisturbed  for  one  or  two  minutes,  when 
the  excess  may  be  cut  away  with  suitable  knives.  Gum  lancet  No. 
2  and  the  discoid  and  cleoid  from  the  ''University  set"  are  service- 
able, as  are  also  the  large  spoon  excavators. 

Removal  of  Matrix.  The  matrix  should  then  be  removed  in  prox- 
imal cavities  by  drawing  to  the  buccal  while  pressing  the  ball  of  the 
finger  gently  on  the  occlusal  surface.  A  loosely  rolled,  rather  large, 
ball  of  cotton  should  be  laid  on  the  amalgam  filling  under  the  finger 
tip,  in  order  to  prevent  the  matrix  from  traveling  occlusally  in  the 
process  of  removal. 

The  rubber  dam  should  then  be  removed  and  the  patient  instructed 
to  slowly  close  the  teeth,  stopping  the  instant  he  feels  the  presence 
of  the  filling  between  the  teeth,  which  will  occur  if  excess  contour 
has  been  built.  With  the  teeth  still  held  in  this  same  position,  the 
patient  is  requested  to  give  the  jaws  a  gentle  side  movement.  This 
will  result  in  burnishing  the  spots  of  contact,  after  which  the  excess 
should  be  whittled  away  with  knife-edged  instruments. 

Amalgam  Should  Be  Cut  From  the  Margins  to  the  filling,  Avhich 
is  just  the  reverse  from  the  travel  of  the  instrument  in  cutting  gold 
fillings.  If  the  cutting  instrument  moves  from  the  filling  to  the  cavo- 
surface  angle  with  amalgam  that  is  only  partially  set,  it  is  liable 
to  sink  too  deeply  into  the  substance  of  the  filling  and  expose  the 
margin  as  it  crosses  over.    . 

Passing  Contact  Point.  In  proximal  fillings  of  amalgam  nothing 
of  any  description  should  ever  be  allowed  to  pass  the  contact  point 
until  the  amalgam  has  completed  the  process  of  setting,  as  one  such 
attempt  forever  destroys  proper  contact  and  a  filling  so  treated  be- 
comes at  once  a  makeshift.  All  overhanging  amalgam  should  be  cut 
away,  around  the  entire  cavity  outline,  but  the  region  of  contact 
point  should  be  entirely  neglected  at  this  time,  and  left  for  final 
shaping  during  the  process  of  polishing.  Finally  the  filling  should 
be  gently  wiped  with  spunk  or  cotton. 


AMALGA:\r    IX    THE    MAKING    OF    A    FILLING  145 

Polishing".  All  nmal^aiu  tillinss  should  i-eeeive  as  thorough  and 
careful  polishing  as  gold.  This  must  he  done  at  a  suhsequent  sit- 
ting. In  proximal  fillings  the  separator  should  l)e  adjusted  and  the 
contact  point  properly  formed  and  polished. 

For  this  work  ahradents  of  only  the  finest  nature  should  he  em- 
ployed. Burs,  carhorundum  stones,  coarse  strips  and  disks  only  do 
harm  and  ])rolong  the  operation.  Fine  stri])s.  disks,  wood  points 
and  leather  wheels,  using  first  pumice  then  whiting,  and  lastly  the 
tooth  polishing  rul)ber  cups  should  he  used. 


CHAPTER  XXIV. 
THE   USE   OF   CEMENTS  IN  FILLING  TEETH. 

Varieties.  There  are  five  main  varieties  of  cement  available  for 
use  in  the  operation  of  filling  teeth;  silicate,  cement,  oxyphosphate 
of  zinc,  oxychloride  of  zinc,  sulphate  of  zinc,  and  oxyphosphate  of 
copper. 

Cavity  Preparation  for  cement  when  the  entire  filling  is  to  be  of 
cement  is  not  unlike  that  for  any  other  filling,  except  that  the  cavo- 
surface  angle  is  left  the  same  as  that  produced  by  the  cleavage  of 
the  enamel,  omitting  the  marginal  bevel.  The  cavity  should  be  given 
the  usual  retention  form,  and  the  matrix  must  be  employed  in  cav- 
ities to  supply  the  missing  wall  that  the  cement  may  be  introduced 
with  pressure  to  condense  and  create  close  adaptation  to  walls. 

The  rules  given  for  dryness  in  the  manipulation  of  gold  and  amal- 
gam are  also  to  be  observed  in  cement  filling. 

The  silicate  cements  have  been  evolved  in  an  effort  to  produce  a 
cement  that  would  more  nearly  harmonize  with  the  color  of  the 
teeth ;  to  better  withstand  the  action  of  the  oral  fluids  and  the  abrad- 
ing effects  of  mastication.  Berylite  is  a  prominent  illustration  of  a 
silicate  cement.  Some  of  the  silicates  are  now  used  as  independent 
fillings  and  are  not  suitable  for  use  as  a  cement.  This  material  as 
a  silicate  filling  is  given  full  consideration  in  Chapter  XXV. 

Oxyphosphate  of  Zinc  has  many  uses  in  the  cavities  of  teeth  as 
a  partial  filling  and  in  some  instances  for  the  complete  filling.  Be- 
ing a  poor  conductor,  it  makes  an  excellent  agent  as  an  intermediate 
between  metal  fillings  and  closely  approached  pulps. 

Its  adhesive  quality  gives  it  great  value  as  a  means  of  adding  re- 
tention to  all  kinds  of  metal  fillings.  This  quality  together  with  its 
harmonious  color  with  tooth  substance  makes  it  invaluable  for  lin- 
ing weakened  enamel  walls  which  have  lost  much  of  their  support- 
ing dentine. 

Its  Chief  Fault  is  its  tendency  to  dissolve  in  the  fluids  of  the 
mouth,  which  renders  it  comparatively  temporary.  However  there 
is  a  considerable  variation  in  its  behavior  in  different  mouths;  in 
some  instances  it  wears  for  years. 

Oxychloride  of  Zinc  is  indicated  in  pulpless  teeth  to  fill  the  pulp 
chamber,  after  the  canals  have  been  previously  filled  with  gutta- 
percha, and  for  the  lining  of  cavities  for  the  preservation  of  color 
where  adhesiveness  is  not   of  importance.     It  is  not  indicated   in 

146 


THE    USE    OF    CEMENTS    IX    FILLING    TEETH  147 

teetli  ^vith  closely  approached  vital  pulp,  or  as  a  root  filling,  on  ac- 
count of  its  irritating  properties. 

Sulphate  of  Zinc,  wlieu  pure,  is  the  least  irritating  of  all  cements 
and  is  one  of  the  best  materials  for  pulp  protection.  A  pulp  cap- 
ping of  this  material  is  of  most  universal  application. 

Oxyphosphate  of  Copper  is  especially  indicated  in  remote  cav- 
ities on  the  necks  of  teeth  occasioned  by  gum  recession.  Cavities 
which  are  so  ill-defined  that  the  use  of  amalgam  or  gutta-percha  is 
difficult,  may  be  successfully  filled  with  this  preparation  of  copper. 

It  can  be  made  to  adhere  very  tenaciously  to  the  walls  of  a  cavity, 
thus  obviating  much  cutting.  Oxyphosphate  of  copper  is  also  in- 
dicated in  the  small  cavities  in  the  deciduous  teeth. 

It  is  claimed  that  this  material  exerts  a  therapeutic  influence  up- 
on the  tooth  substance,  thus  preventing  further  decay. 

Manipulation  of  Oxyphosphate  of  Zinc  Cement.  The  method  of 
mixing  this  cement  is  not  in  the  least  difficult,  yet  certain  details 
are  essential.  The  slab,  preferably  of  smooth  glass,  should  be  clean. 
The  spatula  should  be  flat  with  the  side  slightly  convex. 

Agate  is  the  best  material  as  it  is  not  acted  upon  by  the  liquid. 
The  liquid  and  powder  should  be  placed  upon  the  slab  separately,  the 
drop  of  liquid  being  carried  there  by  the  use  of  a  small  glass  rod. 
The  spatula  should  never  be  immersed  in  the  bottle  to  obtain  more 
fluid  as  this  would  destroy  the  efficiency  of  the  liquid.  Crystallized 
portions  should  be  carefully  wiped  off  the  mouth  of  the  bottle  as 
soon  as  detected. 

Plan  of  Spatulating.  The  powder  should  be  added  to  the  liquid 
a  little  at  a  time  and  each  portion  thoroughly  rubbed  by  a  swinging 
circular  movement  of  the  spatula  upon  the  slab.  This  rubbing  should 
not  be  rapid  or  vigorous.  For  lining  cavities,  where  thin  layers  are 
desired  which  are  very  adhesive,  the  cement  will  prove  correctly 
mixed  when  it  shows  slight  stringiness  and  when  the  first  stickiness 
appears,  as  shown  by  the  slight  resistance  offered  the  spatula  in  its 
movement  over  the  slab.  Where  the  entire  filling  is  to  be  of  cement, 
more  powder  should  be  added  and  the  spatulation  continued  till  the 
cement  materially  resists  spatulation  and  the  mass  is  the  consistency 
of  freshl}^  made  putty.  When  cement  is  of  the  consistency  desired 
no  time  should  be  lost  in  placing  it  in  position,  and  it  should  be 
allowed  to  harden  undisturbed.  If  the  cement  is  to  form  the  en- 
tire filling  and  permanency  is  desired,  it  should  be  crowded  to  place 
with  .some  force  and  rapidly  shaped  up.  As  soon  as  crystallization 
begins  it  should  not  be  disturbed  by  manipulation  till  it  has  fully 
hardened,  when  it  should  he  f)olishfd  wilh  fine  Hlri|)s  jiikI  disks. 


CHAPTER  XXV. 

MANIPULATION  OF  SILICATE  IN  THE  MAKING  OF  A 

FILLING. 

Definition.  Maierials  for  Silicate  Fillings  are  marketed  under 
trade  names  which  no  donbt  snit  the  purposes  of  the  various  manu- 
facturers, and  there  can  be  no  just  criticism  offered  from  the  stand- 
point of  the  tradesman.  However  some  confusion  exists  among  the 
members  of  the  dental  profession  as  to  the  correct  term  to  use  which 
is  broad  enough  to  cover  all  of  this  class  of  fillings  and  not  desig- 
nate any  special  make.  We  will  therefore  consider  some  definitions 
from  Webster's  ''Unabridged  Dictionary." 

Silicate  (a  noun)  "is  a  salt  composed  of  silicic  acid  and  a  base." 
Silicate  from  which  we  make  fillings  is  made  by  silicatization. 

Silicatization  (a  noun)  "is  the  process  of  combining  with  silica, 
so  as  to  change  to  a  silicate,"  which  is,  chemically  speaking,  a  syn- 
thetic process, — "the  uniting  of  elements  to  form  a  compound." 

Porcelain  (a  noun).  "A  fine  translucent  kind  of  earthenware," 
named  after  the  shell  ' '  Porcellana "  "  either  on  account  of  its  smooth- 
ness and  whiteness,  or  because  it  was  believed  to  be  made  from  it." 

Cement  (a  noun)  when  used  as  a  noun  is,  "x\ny  substance  used 
for  making  bodies  adhere  to  each  other,  as  mortar,  glue,  etc." 

Cement  (a  transitive  verb).  "To  unite  by  the  application  of  a 
substance  Avhich  causes  bodies  to  adhere  together." 

Cement  (an  intransitive  verb).  "To  unite  or  become  solid;  to 
unite  and  cohere." 

Cementation  (a  noun).  "The  act  of  uniting  by  a  suitable  sub- 
stance." Chemical  definition:  "A  process  which  consists  in  sur- 
rounding a  solid  body  with  the  powder  of  other  substances,  and  heat- 
ing the  whole  to  a  degree  not  sufficient  to  cause  fusion,  the  physical 
properties  of  the  body  being  changed  by  chemical  combination  with 
the  powder;  thus  iron  becomes  steel  by  cementation  with  charcoal 
and  green  glass  porcelain,  by  cementation  with  sand." 

Enamel  (a  noun).  "A  substance  of  the  nature  of  glass,  but  more 
fusible  and  nearl}^  opaque, — with  a  variety  of  colors;  also  other  ma- 
terials used  for  giving  a  highly  polished  ornamental  surface."  Ana- 
tomical definition:  "The  smooth,  hard  substance  which  covers  the 
crown  or  visible  part  of  a  tooth,  overlying  the  dentine." 

Fi^om  the  foregoing  references  to  Webster  it  would  seem  that  the 
term   "silicate  filling"  is  correct  when  used  to  name  this  kind   of 

148 


silicatp:  IX  the  making  of  a  filling 


149 


filliiio  material  as  a  class  aiul  when  used  to  restore  lost  tooth  sub- 
stance. 

The  use  of  the  word  '■cement"  as  a  part  of  the  name,  hence  a 
noun,  is  incorrect  unless  the  substance  is  used  to  "make  bodies  ad- 
here together"  and  should  be  eliminated  from  the  names  of  the 
silicates  and  other  compounds  intended  for  a  filling  per  se,  except 
when  adhesive  properties  are  taken  advantage  of. 

The  term  "synthetic"  is  correctly  used  when  applied  to  any  of 
the  plastics  now  in  use  in  dentistry,  with  a  possible  exception  in 
amalgam,  as  chemists  are  divided  in  their  opinions  as  to  exactly  what 
takes  place  in  amalgamation.  The  use  of  the  Avord  "Porcelain"  as 
a  part  of  the  name,  its  being  correct  or  incorrect,  depends  entirely 


Fig.   79. 
Fig.   79. — Suitable  cavities  for  the  use   of  silicate  fillings. 


Fig. 


Fig.    80. — A   Class   One   cavity   on   the   labial    of   a   central    incisor   properly   prepared   for   a 
silicate  filling.     The  decays  are   shown   in   Fig.    79. 

upon  our  undei'standing  of  the  degree  of  heat  necessary  to  bring 
about  cementation.  (Sec  definition.)  This  is  accomplished  at  com- 
paratively low  and  ordinary  temperatures  with  most  of  the  makes. 
All  are  assisted  in  the  process  by  temperatures  slightly  above  that 
of  the  body,  with  one  maker  advising  the  melted  jiaraffine  bath  dur- 
ing the  period  of  setting.  The  use  of  the  term  "Enamel"  is  cor- 
rect provided  it  is  a  "substance  of  the  nature  of  glass,  more  fusible. 
nearl.v  opaque,  used  foi'  giving  a  poli.shed  ornamental  surface."  and 
the  prefix  of  "Artificial"  jn-ovided  it  is  "a  sul)stitute"  for  the  nat- 
ural covering  of  a  tooth's  crowiL  Tt  would  seem  that  the  silicates 
are  all  synthetic,  that  they  all    partake  of  the  natui-e  of  poi'celain. 


150 


OPERATIVE    DENTISTRY 


that  they  are  a  trade  enamel,  that  they  are  artificial  when  replace- 
ing  the  lost  enamel  of  human  teeth,  that  they  are  cement 
when  used  to  hold  a  filling  of  other  material  in  the  tooth  or  when 
the  material  itself  adheres  to  the  tooth,  and  that  they  are  not  cement 
(a  noun)  when  used  as  a  filling  per  se. 

The  author  therefore  takes  the  position  that  the  filling  material 
under  consideration  is  ''silicate"  as  the  correct  manipulation  of  most 
makes  eliminates  adhesion  to  the  cavity.  Those  which  adhere  to  the 
cavity  or  will  retain  fillings  of  other  materials  in  the  cavity  are  for 
that  reason  a  silicate  cement.  It  therefore  follows  that  with  the  use 
of  silicate  there  must  be  retentive  form  in  cavity  preparation.     At 


Fig.     81. 


Fig.    82 


Fig.  81. — Extensive  Class  Three  cavity  properly  prepared  for  a  silicate  filling.  Decay 
shown  in  Fig.  79. 

Fig.  82. — A  Class  Five  and  a  Class  Three  cavity  suitable  for  the  use  of  silicate  as  a  filling. 

this  time  we  find  the  best  illustrations  of  this  class  of  silicate  in  "  De 
Trey's  Synthetic  Porcelain"  and  Ascher's  ''Artificial  Enamel," 
neither  of  which  should  be  used  as  a  cement. 

Cavity  Preparation  is  quite  similar  to  that  for  an  amalgam  filling 
and  is  here  considered  in  the  order  of  cavity  procedure. 

Gaining  Access.  The  access  required  for  the  silicate  filling  is  the 
same  as  that  for  any  other  plastic  filling,  as  far  as  its  introduction 
is  considered  and  the  conditions  sought  at  the  time  the  filling  is  com- 
pleted. Contact  point  in  Classes  Two,  Three  and  Four  is  just  as 
essential,  but  is  harder  to  maintain  due  to  interproximal  wear.     It 


SILICATE   IN    THE    MAKING    OF   A   FILLING 


151 


would  therefore  follow  that  the  primary  contact  should  be  greater 
and  broader.  In  other  words,  if  we  are  to  use  the  marble  contact 
it  should  be  the  contacting  of  larger  marbles  than  in  the  more  dur- 
able metal  fillings.  To  put  it  in  other  words,  the  convexity  of  the 
filling's  surface  should  be  the  segment  of  a  larger  circle  than  the 
metal  filling.     Proper  separation  is  essential. 

Outline  Form.  In  the  consideration  of  outline  form,  the  same 
rules  should  apply  as  when  using  any  other  filling.  We  should  ex- 
tend cavity  margins  until  all  surface  decay  has  been  included.  With 
other  filling  materials,  we  sometimes  falter  in  this  because  of  the  un- 
sightly results,  but  with  silicate,  when  the  color  has  been  properly 
chosen,  there  should  be  no  hesitancy,  as  large  fillings  are  generally 


Fig.   83. 


'  Fig.   84. 


Fig.  83. — A  Class  Five  cavity  properly  prepared  for  a  silicate  filling.     The  decay  is  shown 
in  Fig.  82. 

Fig.   84. — A   Class   Three   cavity,   lingual    apjiroach,   properly  prepared    for   a   silicate   filling. 
The  decay  is  shown  in  Fig.  82. 


as  little  observed  as  small  ones,  especially  on  flat  labial  and  buccal 
surfaces.  When  fissures  and  sulcate  grooves  are  encountered,  they 
should  always  be  included  in  the  outline,  as  a  leaky  filling  will  re- 
sult at  the  triangular  space  formed  where  the  sulcate  grooves  meet 
the  filling. 

Resistance  Form.  In  dealing  with  resistance  to  the  crushing 
strain,  wo  have  a  greater  problem  to  solve  than  in  the  use  of  almost 
any  other  material.  The  edge  of  the  filling  is  more  easily  broken, 
and  after  some  months  or  years  of  wear  there  is  great  danger  of  ex- 
posure of  the  cavo-surfacc  angle.     It  is  therefore  necessary  to  lay 


152 


OPERATIVE   DENTISTRY 


Fig.    85.  Fig.    86. 

Fig.  85. — A  small  Class  Three  cavity,  labial  approach,  properly  prepared  for  a  silica'.e  filling. 

Fig.    86. — A   small    Class   Three    cavity,    lingual    apjn-oach,    properly   prepared    for    a    silicate 
falling. 


Fig.   87. 


Fig.   88. 


Fig.  87. — A  large  Class  Three  cavity,  labial  approach,  properly  prepared  for  a  silicate  filling. 
Note  the  irregular  outline  on  the  lalsial.  This  is  not  objectionable,  for  many  times  an  ir- 
regular outline  hides  a  sli.ght  deviation  from  the  proper  color. 

Fig.  88.- — A  large  Class  Three  cavity,  lingual  approach,  properly  prepared  for  a  silicate 
filling.  Note  the  fact  that  this  cavity  has  two  axial  wails.  This  is  a  good  form  of  preparation 
in  vital   cases. 


SILICATE    IN    THE    MAKING    OF   A    FILLING 


153 


the  cavity  outline  in  areas  subject  to  as  little  stress  as  possible. 
In  locations  subject  to  great  liability  to  stress,  it  is  necessary  to  ex- 
tend the  outline  until  full-lenoth  enamel  rods,  supported  by  sound 
dentine,  have  been  reached  and  then  beyond  that  to  a  location  not 
subject  to  the  travel  of  the  cusps  of  opposing  teeth  in  the  process 
of  articulation.  It  is  not  necessary  to  pay  much  attention  to  devel- 
opmental grooves,  for  when  these  grooves  are  normally  formed  they 
are  fully  as  strong  as  the  material  in  hand.  It  is  most  important 
that  all  enamel  eminences  be  avoided,  as  the  material  is  quite  friable 
and  offers  very  little  support  to  the  cavo-surface  angle. 

Retention  Form.     Provision  against   the  tipping  strain    is    the 
same  as  for  other  fillings  and  is  more  like  that  for  amalgam.     This 


Fig.   89. 


Fig.   90. 


Fig.  89. — A  large  Class  Three  civity  |)ropcrly  jjreiiarcd  for  a  silicate  filling.  Note  the 
small  amount  of  dentine  yet  remaining  near  the  incisal  angle.  While  this  angle  can  inoperly 
remain  when  using  a  silicate  filling,  it  would  be  entirely  out  of  the  question  when  using  co- 
hesive gold. 

Fig.  90. — Two  extensive  Class  Three  cavities  projjcrly  prepared  for  silicate  fillings.  In  both 
of  these  cavities  the  dentine  has  been  practically  all  removed  at  the  incisal  angles.  Cases  like 
these  may  be  filled  with  silicate  but  should  be  regarded  as  temjjorary  in  a  large  majority  of  the 
cases.  The  retention  of  these  angles  after  filling  will  depend  entirely  upon  the  amount  of 
force  to  which  they  were  subjected.  They  would  be  comparatively  permanent  in  cases  of  ir- 
regularity when  that  condition  [)laced  these  angles  in  a  position  removed  from  stress  in  oc- 
clusion and  articulation. 


material  only  reaches  its  maxiniuiii  strength  to  resist  dissolution  and 
the  crushing  strain  when  it  has  been  so  thickly  mixed  that  it  has 
lost  practically  all  of  its  adhesive  (|ualities.  Therefore,  the  rules 
which  apply  to  cavity  pi'cpai'ation  in  refci'cnce  to  retention  form 
would  be  the  same  as  in  the  use  of  amalgam.  We  must  have  flat 
walls  excepting  the  axial,  flat  seats  of  generous  pi'o[)oi'tioiis  and  def- 
inite angles. 


154 


OPERATIVE   DENTISTRY 


Convenience  Form.  This  step  in  cavit^^  preparation  for  the 
silicate  filling,  as  with  other  plastics,  comes  in  for  only  a  minimum 
consideration,  as  it  is  seldom  necessary  in  the  use  of  this  material 
to  make  any  changes  to  facilitate  the  making  of  the  filling,  for  when 
other  rules  have  been  followed  we  find  ample  convenience  for  its  in- 
troduction. 

Removal  of  Remaining'  Decay.  There  is  one  major  reason  why 
all  softened  dentine  should  be  removed  from  the  cavity  walls.  The 
decalcified  portion  of  tooth  substance  is  always  saturated  with  the 
acid  of  tooth  decay, — ^lactic  acid.  Experience  has  proved  that  the 
crystallizing  silicate  will  absorb  this  acid,  resulting  in  a  filling  of 
weak  structure.  It  would  therefore  follow  that  no  softened  dentine 
be  allowed  to  remain  in  the  cavity. 

Finishing-  of  Enamel  Walls.    With  other  fillings  it  has  been  found 


-     -" 

— 

<~ 

J, 

MSH^Bfliii  i !  iMiiiirfiiiiBiltBnilT^ 

3 

:^ 

^ 

^-•^Si' 

IRk_ 

fcMtt^fn  1- 

.^..^■r 

^^^^ 

fifl^" 

^^jL 

Wi     ■-??--5*3?^- 

— -;•— ^srr 

^^^^^ 

Fig.  91. — A  small  set  of  instrumencs  for  manipulating  silicate. 


advisable  to  bevel  the  enamel  margins  from  6  to  10  degrees  centi- 
grade. With  all  silicate  fillings,  this  beveling  seems  to  make  an  ad- 
ditional weakness  and  should  be  avoided  as  it  will  cause  the  filling 
to  break  at  the  margin,  even  though  the  procedure  results  in  an  im- 
perfect cavity,  from  a  scientific  standpoint.  "We  should  determine 
that  we  have  full-length  rods  and  that  we  have  found  their  direc- 
tion by  complete  cleavage  and  then  omit  the  beveling. 

Toilet  of  the  Cavity.  To  the  ordinary  toilet  given  for  other  fill- 
ings should  be  added  the  varnishing  of  the  dentine  walls,  as  a  pre- 
caution against  the  material  absorbing  either  acid  or  moisture  from 
the  walls  or  the  absorption  by  drying  dentinal  walls  of  the  fluid 
part  of  the  filling,  due  to  excessively  desiccated  dentine. 

Rubber  Dam.  The  application  of  the  rubber  dam,  or  other  means 
equally  as  efficient,  should  have  taken  place  following  partial  outline 


SILICATE   IN    THE    MAKING   OF   A   FILLING 


155 


form.  Prior  to  adjusting  the  rubber  dam,  the  color  or  combination 
of  colors  should  have  been  selected,  as  the  opinion  formed  after  the 
rubber  dam  has  been  in  place  for  a  short  time  is  worthless  as  a  guide 
to  the  proper  shade  to  be  used.  During  the  early  experience  with 
this  material,  with  each  operator,  the  shade  guide  should  be  fre- 
quently used  as  an  educator,  but  in  a  few  months,  the  operator  should 
begin  to  be  so  familiar  with  the  resulting  colors  that  no  shade  guide 
is  necessary. 

Making"  the  Filling".     When  cavity  preparation  is  completed,  the 
proper  material  and  instruments  for  making  the  filling  should  be 


Fig.  92. — A  suitable  slab  and  spatula  for  working  silicate.  The  slab  should  be  thick  and 
heavy  in  order  that  when  chilled  it  will  remain  at  a  low  temjierature  during  the  mixing  of 
the  silicate. 


placed  in  a  handy  position.  Absolute  cleanliness  is  imperative,  par- 
ticularly during  the  process  of  mixing,  as  otherwise  the  filling  when 
completed  will  not  be  chemically  pure.  The  mixing  slab  should  al- 
ways be  kept  scrupulously  clean,  should  not  have  a  scratched  sur- 
face and  should  be  without  color.  This  last  point  is  to  avoid  any 
effect  color  could  have  on  the  judgment  as  to  the  shade  desired.  A 
good  slab  is  produced  by  taking  a  large-mouthed  bottle  and  filling 
it  with  cold  water,  or  even  ice  water,  in  order  that  during  manipula- 
tion the  material  may  be  held  at  a  low  temperature.  Before  using  a 
thick  glass  slab  (Fig.  92)  chill  to  a  temperature  of  GO  degrees  or  a 
little  below.  The  temperature  feature  in  this  manipulation  is  of 
imj)ortance.  With  nearly  all  of  the  pi-ocesses  in  the  filling  of  teeth 
wherein  the  dentist  depends  upon  sul)sequent  chemical  action  for 


156 


OPERATIVE    DENTISTRY 


a  final  result,  cheinical  action  should  be  either  retarded  or  held  in 
check  during  the  entire  process  of  manipulation,  which  is  easily 
accomplished  by  a  low  temperature  mix.     "The   process   of  set- 


Fig.    93. — Proper  position   of   the   spatula   on    the   slab   when   manipulating   silicate. 


Fig.   94. — Proper  placing  of  the  materials  when  manipulating  silicate. 

ting"  as  it  is  called  is  held  in  check  until  the  material  is  finally  in 
place  and  further  disturbance  unnecessary.  As  soon  as  the  filling 
has  been  placed  in  the  tooth,  the  warmth  of  the  body  is  sufficient 


SILICATE    IX    THE    MAKING    OF    A    FILLING 


157 


to  hasten  the  eheiuieal  action  and  l:)etter  results  Avili  be  secured. 
"With  most  of  the  silicate  fillings,  the  body  temperature  is  suf- 
ficient: with  others  tlie  best  i-esult  can  only  be  obtained  by  keeping 


Fig.    95. — Taking    the    first    portion    of    the    i)0\vder    whic'i    should    bi-    aliout    half    of    the    entiri 

amount   needed. 


I-'ig.   96.  —  fncorporatinf;  the   first   portion   of  the  powder. 


llic  filling  for  a  sliiot  time  biillictl  in  nu'ltcd  pai-aflinc.  Tlu'  mix- 
ing slal)  slionbl  be  ill  as  b)\\'  a  Icnipcrjil  urc  as  i)ossibb'  and  shonbl  not 
}»i-odiicc  disconililnrc  to  Ihc  palicnl.     A  Icnijx'ralui'c  of  (iO  degrees 


158 


OPERATIVE   DENTISTRY 


seems  to  be  as  low  as  can  be  borne  by  the  patient  when  placing  a 
filling  in  a  vital  tooth.  It  is  therefore  quite  practical  to  use  a 
bottle  slab  wherein  the  thermometer  reaches  55  to  60  degrees,  as  no 
doubt  the  temperature  of  the  filling  is  about  68  when  placed  in  the 
tooth.  It  is  quite  possible  to  use  a  bottle  that  contains  iced  water 
when  the  filling  is  to  be  placed  in  a  non-vital  tooth.  .At  such  times 
when  the  atmosphere  is  close  to  the  dew  point,  as  is  evidenced  by 
the  condensation  on  the  fountain  cuspidor,  there  will  be  trouble 
about  the  formation  of  moisture  on  the  cold  bottle.  .  When  this  is 
only  slight,  it  does  not  seem  to  damage  the  filling.  However,  when 
the  condensation  is  sufficient  to  be  noticed,  or  is  excessive,  the  den- 
tist has  to  either  content  himself  with  manipulation  at  a  higher 
temperature  or  postpone  the  operation  to  a  time  when  the  atmos- 
phere is  above  the  dew  point.  The  spatula  must  be  of  some  ma- 
terial which  will  give  off  none  of  its  substance  during  the  process 
of  mixing.    For  this  reason  the  agate  is  the  best  and  most  popular. 


Fig.  91. — Illustrating  the  circular  motion  which  should  be  given  the  spatula  in  mixing  a 
silicate  filling.  Note  that  the  spatula  should  be  moved  first  in  one  direction  and  then  in  the 
other  as  indicated  by  the  arrows.  Also  that  the  spatula  describes  segments  of  small  circles 
and  that  the  material  is  not  spread  over  any  considerable  surface  of  the  slab. 


Begin  the  mixing  only  when  the  cavity  is  prepared  and  dried,  and 
the  filling  instruments  are  laid  out  and  ready  for  immediate  use. 
While  there  is  no  great  haste  as  long  as  the  material  lays  on.  the 
cold  slab,  there  are  left  but  a  few  seconds  to  make  the  filling  after 
the  material  has  been  removed  from  the  slab,  on  account  of  the 
rising  temperature  hastening  chemical  action. 

Preparing  Materials.  First  pour  out  near  the  end  of  the  slab  to 
the  right,  the  amount  of  powder  the  mix  is  liable  to  require,  and 
then  place  stopper  in  the  bottle.  With  the  dropper  place  the 
proper  quantity  of  liquid  near  and  to  the  left  of  the  powder.  Im- 
mediately return  the  dropper  to  the  bottle  and  secure  the  cap  to 
prevent  evaporation.  The  best  results  are  obtained  when  no  less 
than  three  drops  of  liquid  are  used  for  the  mix.  Do  not  shake  the 
liquid  bottle.  Make  the  mix  promptly,  for  if  there  is  any  consider- 
able delay,  the  chemical  formula  of  the  liquid  may  be  changed,  due 


SILICATE   IX   THE    MAKING   OF   A   FILLING 


159 


to  an  evaporation  in  a  dry  atmosphere  or  the  addition  of  water 
in  taking  np  the  condensation  from  the  cold  slab  at  low  barometer. 
Making-  the  Mix.  Begin  ^^'ith  sufficient  liquid  on  the  slab  and  do 
not  add  any  more  at  that  stage.  Mix  by  drawing  into  the  liquid 
about  one-half  of  the  total  amount  of  powder  required  to  make  the 
completed  filling.  Begin  the  mix  by  spatulating  with  a  light  rotat- 
ing movement ;  hold  the  spatula  flat  on  the  slab,  describing  the 
arc  of  a  small  circle  with  a  diameter  of  say  one-fourth  of  an  inch. 
As  soon  as  the  poM'der  has  been  all  incorporated  and  the  mass  ren- 
dered uniform,  scrape  all  of  the  mass  off  the  slab  with  about  three 
strokes.  Take  one-third  of  the  mix  each  time.  This  assists  in  se- 
curing uniformity  of  the  mass.     Then  put  it  back  on  the  slab  this 


Fig.  98. — The  last  stroke  of  scraping  the  material  from  the  slab. 

time  getting  all  off  the  spatula.  Do  not  scrape  the  spatula  on  the 
edge  of  the  slab,  but  place  it  flat  on  the  slab,  holding  it  firmly 
and  giving  it  a  turn  in  the  hand,  Avhich  will  practically  clean  it. 
Here  more  powder  is  added,  a  small  portion  at  a  time,  and  incor- 
porated in  the  mass  already  mixed,  by  the  method  of  crowding, 
which  is  done  by  rolling  the  spatula  first  against  one  side  of  the 
mass  on  the  slab  and  then  against  the  other.  The  addition  of  the 
powder  by  this  crowding  process  is  continued  until  the  mass  l)e- 
comes  of  a  consistency  of  putty,  losing  practically  all  of  its  adlie- 
sion  and  giving  only  slight  evidence  of  a  tendency  to  follow  the 
spatula  from  the  slab. 

The  Proper  Consistency  is  reached  when  the  mass  has  been  mixed 


160 


OPERATIVE    DENTISTRY 


SO  stiff  that  the  material  just  loses  its  gloss  when  being  crowded  by  a 
rotating  spatula,  yet  can  be  made  to  show  a  glossy  surface  when  patted 
three  or  four  blows  with  the  spatula.  In  case  the  material  looks  very 
wet  and  glossy  the  mix  is  not  yet  stiff  enough.  If  the  three  or  four 
blows  do  not  produce  gloss,  the  mix  is  too  heavy  and  must  be  entirely 
discarded. 

Time  of  the  Mix.  The  lower  the  temperature  at  which  the  sili- 
cate is  mixed  the  longer  may  be  the  time  of  manipulation ;  also 
the  thinner  the  mix,  the  longer  wdll  it  be  before  the  chemical  ac- 
tion of  the  setting  will  be  noticed.  By  using  the  cold  process  of 
mixing,  the  time  of  manipulation  is  lengthened  and  the  time  of  set- 


rig.   99. — The   entire  mix   on   the  spatula. 


\ 


i.^ 


Fig.   100. — Illustrating  in  three  successive  steps  the  method  of  removing  the  mix  from  the 

spatula  to  the  slab. 

ting  after  leaving  the  slab  is  materially  shortened,  due  to  the  thick 
mixture  obtainal^le. 

Making  the  Filling.  It  is  important  that  all  moisture  be  ex- 
cluded, as  we  cannot  manipulate  silicate  under  moist  conditions. 
Agate  or  ivory  instruments  are  preferred  for  placing  the  material 
in  the  cavity.  Those  of  bone  or  shell  will  do.  If  the  instruments 
are  absolutely  clean  and  polished  so  that  they  wall  give  off  no  sub- 
stance in  the  material,  it  is  possible  to  place  the  silicate  in  the  cav- 
ity with  steel  instruments  and  get  no  subsequent  discoloration. 
Fill  the  cavity  slightly  to  excess  with  absolutely  clean  instruments 
by  taking  a  quantity,  one-half  of  that  required  to  fill  the  cavity, 
and  crowd  or  wipe  the  material  against  every  portion  of  the  cavity 
walls  from  cavo-surface  angle  to  cavo-surface  angle.  The  second 
time,  take  up  a  sufficient  quantity  to   more  than  fill  the   cavity. 


SILICATE    IX    THE    MAKING    OF    A    FILLING 


161 


Crowd  this  into  position  and  hastily  get  a  partial  contour.  Ini- 
niediately  pat  or  paddle  the  material  to  complete  contour,  continu- 
ing until  the  material  has  been  crowded  slightly  over  the  margins. 
This  paddling  force  will  jar  the  material  so  as  to  bring  back  the  gloss, 
as  produced  by  patting  on  the  slab.  In  case  the  gloss  is  not  produced 
by  the  paddling,  a  homogeneous  mass  is  not  secured  and  the  fill- 


Fig.    lijl. — i'loijcr   (.oiisistency    of   silicate,    for   inimcdialc   introduction    into   the   cavitv 


Fig.  102. — This  mix  of  silicate  is  yet  too  thin  and  there  should  be  more  powder  added. 
The  material  should  show  a  tendency  to  follow  the  spatula  when  moved  from  the  slab  but  it 
should  not  follow  the  sjotula  as  here  shown. 

ing  will  lack  proper  cobir,  will  be  of  poor  edge  strength,  and  will 
make  a  very  weak  filling.  Jf  the  glo.ss  has  ])0("ii  i)roduced  by  the 
paddling  or  jarring  of  the  material,  it  should  be  allowed  to  remain 
undisturbed  until  the  process  of  setting  has  sufficiently  taken  place 
that  the  body  of  Uic  filling  will  not  be  moved  l)y  any  work  ii])on 
its  surface. 


162 


OPERATIVE   DENTISTRY 


The  Use  of  the  Matrix  either  upon  the  posterior  or  anterior  teeth 
should  be  the  same  as  that  for  the  introduction  of  the  amalgam 
filling.  With  Class  Three  fillings,  one  end  of  the  matrix  is  left 
loose  until  the  cavity  has  been  filled  more  than  full  with  the  ma- 
terial. The  loose  end  is  then  brought  over  the  tooth  and  tapped  on 
the  outside  of  the  surface  as  it  is  being  tightened  upon  the  filling. 
This  jarring  process  of  bringing  the  matrix  to  position  results  in  a 
homogeneous  mass  beneath  the  matrix.  Immediately  after  pad- 
dling the  filling  and  the  detection  of  the  glossy  surface,  the  filling  is 
to  be  entirely  coated  with  cocoa  butter  to  exclude  the  air  during 
the  process  of  setting. 

Finishing-  the  Filling-.  After  the  filling  has  been  allowed  to  stand 
undisturbed  for  three  or  four  minutes  (no  longer),  there  should  be 
applied  a  very  thin-edged  knife  or  chisel  and  by  a  scraping  motion 


Fig.  103. — A  homemade  mallet  and  point  used  by  the  author  in  paddling  and  jarring 
silicate  to  position  in  the  cavity.  The  mallet  should  be  of  light  weight  and  have  a  soft  sur- 
face. The  plugger  point  here  shown  is  made  of  platinized  gold.  Tandilum  would  be  better 
for  this  provided  it  had  a  handle  attached  which  was  of  very  light  material.  It  is  quite  neces- 
sary in  this  process  that  both  hammer  and  plugger  point  are  of  the  least  possible  weight. 

parallel  with  the  cavity  outline  the  excess  is  cut  away  to  within 
one-tenth  of  a  millimeter  of  the  cavo-surface  angle,  at  the  same 
time  reducing  the  general  contour  to  that  desired,  keeping  the 
filling  submerged  in  the  cocoa  butter.  When  the  filling  has  been 
in  position  five  or  six  minutes,  very  fine  strips  or  disks  coated  with 
cocoa  butter  may  be  used  to  produce  the  desired  gloss.  The  author 
prefers  to  leave  the  filling  with  file  and  knife  finish  and  has  aban-' 
doned  the  use  of  strips  and  discs  as  injurious.  This  completed 
filling  should  be  scrubbed  with  cotton  balls  in  order  to  remove  all 
of  the  cocoa  butter  possible  and  the  finished  filling  painted  with  a 
copal-ether  varnish.  No  varnish  of  which  alcohol  is  a  part  should 
be  used.  Evaporate  to  dryness  with  air,  remove  the  rubber  dam 
a.nd  test  for   occlusion   and   articulation,   provided   the   filling   in- 


SILICATE    IX    THE    MAKING    OF    A    FILLING 


163 


volves  the  occlusal  or  incisal  surfaces.  In  case  the  filling  is  found 
to  strike  the  apposing  teeth,  the  excess  should  be  ground  off  with 
fine  carborundum  wheels,  and  again  varnished.  It  is  entirely  safe 
to  use  carbon  paper  to  print  these  fillings,  the  same  as  with  gold 
or  amalgam  and  its  use  will  not  cause  discoloration  of  the  filling. 
The  instruments  used  in  reducing  the  size  of  silicate  fillings  should 
be  the  same  as  when  reducing  the  bulk  of  a  gold  filling.  The 
manufacturers  of  some  of  the  silicates  advise  not  to  use  any  steel 


Fig.    104. 
Fig.   104. — Three  cavities  suitable  for  silicate  fillings. 


Fig.    105. 


Fig.  105. — This  shows  the  results  obtained  after  filling  with  silicate  the  cavities  shown  in 
previous  figure. 

instruments  in  the  finishing  of  these  fillings,  but  clinical  experi- 
ence has  proved  that  any  injury  Avhich  can  result  is  not  due  to  the 
instruments,  but  to  their  unclean  condition. 

Facing  Metal  Fillings  with  silicate  is  many  times  of  advantage 
and  is  at  this  time  tlie  only  method  wherein  it  is  advisable  lo  use 
silicate  in  connection  with  angle  restoration  in  Class  Four  fillings. 
This  will  be  more  fully  discussed  in  Chapter  XXVIII  dealing  with 
Combination  Fillings.     (Sec  Figs.  lOG,  107  and  108.) 


CHAPTER  XXVl. 
THE  USE  OF  GUTTA-PERCHA  IX  FILLING   TEETH. 

Gutta-Percha  has  its  place  in  various  operations  upon  the  teeth. 
It  is  not  acted  upon  by  the  fluids  of  the  mouth  and  is  quite 
permanent  when  placed  in  locations  protected  from  the  force  of 
mastication. 

It  is  a  good  tooth  preserver  as  decay  does  not  readily  take  place 
in  cavities  so  filled. 

Base  Plate  Gutta-Percha  is  the  best  form  to  be  had.  It  comes  in 
the  -white  and  pink  colors,  the  last  named  being  the  most  dur- 
able in  positions  exposed  to  wear  as  it  gets  the  harder  upon  cooling. 

Filling-  Cavities  with  Gutta-Percha.  This  material  is  indicated 
in  subgingival  cavities,  both  buccal  and  proximal,  where  a  fill- 
ing that  is  a  very  poor  conductor  of  heat  is  desired,  on  account  of 
close  proximity  to  the  pulp,  the  pulp  being  not  yet  exposed. 

It  is  also  indicated  for  those  distressing  cases  where  there  is  a 
decay  started  in  the  occlusal  surface  of  a  lower  third  molar  which 
has  erupted  with  its  occlusal  surface  at  an  angle  of  about  forty- 
five  degrees  to  the  distal  of  the  second  molar.  Such  cases  cannot 
as  a  rule  be  properly  extended  to  cheek  decay  in  the  use  of  amal- 
gam or  gold. 

The  gutta-percha  filling  will  check  decay  and  if  renewed  at 
stated  periods  will  produce  sufficient  separation  for  correct  filling 
or  to  render  extraction  easy. 

Method  of  Preparation  and  Filling.  The  cavity  should  be  freed 
of  all  decay  and  the  cleavage  of  the  enamel  secured,  omitting  the 
marginal  bevel.  The  cavity  should  be  sterilized  and  dried,  then 
slighth'  moistened  with  campho-phenique  or  eucalyptol.  The 
gutta-percha  should  then  be  warmed  and  immediately  crowded  to 
position.  Care  should  be  taken  that  the  material  is  not  overheated 
as  slight  burning  destroys  the  durability  of  rubber. 

The  gutta-percha  should  be  introduced  piece  by  piece  sufficient 
to  a  little  more  than  fill  the  cavity.  The  surplus  must  be  wiped  off 
flush  with  the  cavity  margins  with  warmed  burnishers.  Finally 
the  surface  should  be  wiped  with  a  cotton  ball  carrying  chloro- 
form. 

For  Root  Canal  Fillings.  The  gutta-percha  is  dissolved  in  chloro- 
form to  the  consistency  of  molasses,  and  carried  to  the  canals  by 

164: 


GUTTA-FERCHA   IN    FILLING    TEETH  165 

dipping  a  smooth  broach  in  the  container.  The  canals  should  have 
been  previously  flooded  Avith  oil  of  eucalyptol,  and  the  chlora- 
percha  mixed  with  the  eucalyptol  in  the  root  canal  resulting  in 
Avhat  may  be  termed  euco-percha.  The  eucalyptol  may  be  added 
to  the  chlora-percha  in  the  bottle,  but  the  method  given  first  is  for 
various  reasons  the  better. 

For  Canal  Points.  Gutta-percha  is  the  standard  material  for 
canal  points  Avhich  should  be  at  hand  in  various  sizes  to  suit  all 
oases. 

These  may  be  manufactured  by  the  dentist,  but  with  little  econ- 
omy, as  they  are  well  made  by  machinery.  Tliose  Mhich  are  flat- 
tened on  the  larger  end  are  the  most  handy  to  use.  Such  may  be 
had  from  your  dealer,  or  the  assistant  can  flatten  them  as  pur- 
chased by  placing  them  on  a  glass  mixing  slab  and-pressing  each 
larLi-e  end  Avith  a  smooth  cold  steel  instrument. 

Slow  Separation.  Gutta-percha  for  slow  separation  in  proximo- 
oeclusal  cavities  is  unexcelled,  the  force  of  mastication  doing  the 
Avork  sloAvly  but  surely.  This  fact  prohibits  the  use  of  gutta- 
percha as  a  permanent  filling  in  Class  Tavo  cavities. 

Temporary  Stopping,  as  purchased  from  the  dealer,  is  gutta- 
percha to  Avhich  Avax  has  been  added  to  render  it  more  plastic 
Avhen  Avarmed.  This  is  ideal  for  sealing  in  dressings,  excepting 
when  arsenic  has  been  used,  in  Avhich  ease  poorly  mixed  amalgam 
is  better. 


CHAPTER  XXVII. 
TIN  AS  A  FILLING  MATERIAL 

History.  The  first  use  of  tin  as  a  material  for  filling  teeth  would 
seem  to  date  back  to  about  1780  and  was  much  written  about  as 
a  tooth  preserver  for  the  century  following.  After  the  introduc- 
tion of  amalgam  in  1826  there  seemed  to  have  been  much  rivalry 
between  the  two  substances,  amalgam  gaining  the  favored  position. 

At  the  World's  Columbian  Dental  Congress,  in  Chicago,  1893,  as 
will  be  seen  by  the  report,  many  dentists  of  national  repute  went 
on  record  as  classifying  tin  as  one  of  our  best  tooth  savers  and  de- 
plored the  fact  that  its  value  was  being  lost  sight  of. 

The  late  Dr.  W.  C.  Barrett  expressed  himself  so  emphatically  as 
to  say,  ' '  Tin  is  as  cohesive  as  gold,  and  if  everything  were  blotted 
out  of  existence  with  which  teeth  could  be  filled,  except  tin,  more 
teeth  would  be  saved."  This  may  be  putting  it  a  little  too  strongly, 
but  the  fact  remains  that  more  teeth  would  be  permanently  saved 
if  a  more  general  use  of  tin  was  common  with  the  profession  today. 

Therapeutic  Value  of  a  Tin  Filling-.  Of  all  our  filling  materials 
there  are  only  two  for  which  any  therapeutic  value  is  claimed. 
All  others  prevent  the  farther  loss  of  tooth  substance  by  exclusion ; 
mechanically  shielding  the  defenseless  tooth  substance  from  the 
dissolving  properties  of  the  products  of  fermentation. 

The  Therapeutic  Action  of  Tin  is  probably  due  to  the  formation 
of  the  sulfid  of  tin  which  is  caused  by  the  presence  of  sulfuretted 
hydrogen  from  the  decomposition  of  food  substance.  The  dentinal 
walls  of  a  cavity  which  has  been  filled  with  tin  for  some  time,  turn 
brown  or  black  and  seem  to  have  undergone  a  structural  change 
rendering  them  quite  impervious  to  decay,  and  very  hard  to  ex- 
cavate with  hand  instruments  or  the  engine  bur. 

Discoloration.  In  some  mouths  tin  turns  black  not  only  upon 
its  external  surface  but  this  color  is  in  a  measure  transmitted  to 
the  tooth  substance,  a  fact  which  is  one  of  the  greatest  objections 
to  its  use  and  debars  it  from  exposed  positions  in  the  anterior  por- 
tion of  the  mouth.  In  other  mouths  there  seems  to  be  little  dis- 
coloration, the  filling  remaining  polished  and  of  a  light  color. 

The  Amount  of  Discoloration  seems  to  bear  no  relation  to  its 
permanency  as  to  bulk  or  as  a  tooth  preserver. 

Thermal  Conductivity.     Tin  is  only  one-fourth  as  good  a  con- 

166 


TIN    AS    A   FILLING    MATERIAL  167 

ductor  of  heat  as  gold,  hence,  indicated  under  gold  fillings  in  deep- 
seated  caries  Avith  vital  pulp. 

Indicated  in  Rapid  Caries.  In  caries  of  a  light  or  Avliite  color 
indicating  the  most  rapid  form  of  decay,  tin  is  of  peculiar  advan- 
tage, particularly  in  regions  removed  from  view  and  protected 
from  the  wear  of  mastication. 

Tin  in  the  Teeth  of  Children.  There  is  no  better  material  for  fill- 
ing the  teeth  of  children  than  tin.  The  principle  of  mechanical  ex- 
clusion depended  upon  with  other  filling  materials  to  prevent  re- 
current decay  does  not  seem  to  be  sufficient  in  the  rapid  form  of 
decay  met  with  in  both  temporary  and  permanent  teeth  in  the 
mouths  of  children  particularly  during  the  age  of  rapid  develop- 
ment as  found  before  the  age  of  fifteen  or  sixteen.  The  additional 
advantage  of  the  therapeutic  influences  of  tin  seems  to  be  sufficient 
to  check  this  rapid  progress  of  decay  till  a  period  is  reached  when 
the  process  of  tooth  destruction  is  less  apparent,  due  to  more  hy- 
gienic conditions  in  the  oral  cavity. 

Cavity  Preparation  for  Tin.  The  cavity  preparation  for  the  use 
of  tin  is  not  unlike  that  given  in  the  chapters  on  cavity  prepara- 
tion by  classes  for  cohesive  gold.  It  will  be  of  advantage  if  the 
convenience  angles  are  a  little  more  distinct,  and  the  general  re- 
tentive form  throughout  should  be  emphasized.  The  bevel  angle 
should  be  a  little  more  deeply  buried  as  the  edge  strength  is  not 
as  good  as  hammered  gold.  However  the  edge  strength  is  better 
than  amalgam.  Tin  has  no  tendency  to  spheroid  like  amalgam. 
Its  flow  is  similar  to  that  of  gold  but  gi-eater  with  the  same  given 
load  and  like  gold  it  is  capable  of  being  so  condensed  that  it  will 
stand  repeated  stress  of  a  given  load  within  a  limited  range  and 
shoAv  no  flow. 

Forms  of  Tin.  Formerly  the  only  form  of  tin  to  be  had  for  this 
purpose  Avas  the  sheet  tin.  This  was  manipulated  in  much  the 
same  way  as  cohesive  gold  except  that  it  required  no  annealing. 

It  was  then,  and  is  yet,  sometimes  combined  with  gold  by  rolling 
a  sheet  of  pure  tin  with  a  sheet  of  annealed  cohesive  gold  into 
rolls,  the  gold  on  the  outside  and  condensed  in  the  usual  manner 
using  a  large  proportion  of  hand  pressure. 

At  present  there  is  on  the  market  a  form  of  tin  prepared  in  the 
shreds,  which  appears  like  a  mass  of  coarse  silver-colored  hair. 
This  is  removed  from  the  tube  and  shaped  into  pellets  of  suitable 
size  and  placed  in  the  cavity  in  the  manner  one  would  place  pellets 
of  gold. 

Methods  of  Introduction.     Tlio  lubbci-    flnm    or    other    efficient 


168  OPERATIVE  DENTISTRY 

means  of  dryness  must  be  used.  When  one  of  the  surrounding 
walls  is  missing  as  in  proximo-occlusal  cavities  in  bicuspids  and 
molars  (Class  Two)  the  matrix  must  be  in  place.  The  first  pellet 
of  tin  introduced  should  completely  cover  the  base  of  cavity  and 
be  thoroughly  condensed  by  good  steady  hand  pressure,  with 
points  at  least  one  square  millimeter  in  size  employing  the  rock- 
ing motion.  The  points  should  have  deep  serrations  and  be  so  stepped 
as  to  include  the  entire  surface. 

This  hand  pressure  should  be  followed  with  the  mallet  force 
using  a  plugger  point  of  medium  serrations  and  the  surface  en- 
tirely gone  over.  A  new  pellet  may  now  be  applied  and  the  plan 
just  given  repeated.  If  the  filling  is  to  be  entirely  of  tin  the  cavity 
should  be  filled  to  excess  and  by  a  process  of  burnishing,  con- 
densed and  rubbed  to  the  size  desired.  This  last  method  gives  a 
surface  of  the  greatest  density  possible. 

Tin  and  Gold.  When  the  filling  is  to  be  completed  with  cohesive 
gold  little  dependence  should  be  put  upon  the  gold  adhering  to  the 
tin  as  the  union  is  only  slight.  With  a  round-pointed  instrument 
new  convenience  angles  should  be  made  in  the  substance  of  the 
tin  near  the  line  angles.  The  remainder  of  the  cavity  should  be 
retentive  independent  of  the  space  occupied  by  the  tin. 

Tin  and  Amalgam.  No  special  care  is  needed  when  the  filling  is 
to  be  completed  with  amalgam.  Amalgamation  takes  place  in  that 
portion  of  the  tin  next  to  the  amalgam  proper  and  the  union  is 
quite  strong,  even  more  than  tin  to  tin.  The  amalgam  should,  if 
possible,  be  more  thoroug?dy  mixed  and  the  process  of  kneading 
prolonged  that  all  amalgamation  possible  be  secured  before  con- 
tacting with  the  tin  as  the  tin  will  take  up  some  of  the  mercury 
from  the  amalgam  for  which  it  has  a  great  affinity.  This  is  liable 
to  injure  the  amalgam  as  to  strength  unless  the  mixing  has  been 
thorough.  The  use  of  tin  and  amalgam  is  not  advised  where  the 
surface  of  the  tin  is  to  be  exposed  by  forming  any  portion  of  the 
contour  as  the  presence  of  the  mercury  absorbed  causes  the  tin  to 
rapidly  disintegrate.  Gold  should  be  used  for  topping  in  such 
cases. 

Tin  in  Bifurcated  and  Punctured  Roots.  When  through  decay 
or  by  accident  the  cavity  extends  to  the  exposure  of  the  peridental 
membrane  the  use  of  tin  has  no  substitute.  The  opening  should 
be  rendered  as  clean  as  possible,  sterilized  and  dried.  The  open- 
ing should  be  covered  with  a  mat  of  pure  tin  made  from  foMed 
sheets,  being  lightly  burnished  to  place  and  covered  with  amal- 
gam and  the  cavity  finished  with  the  desired  material. 


CHAPTER  XXVIII. 
COMBINATION  FILLINGS 

Definition.  A  eoinbinatioii  filling  is  a  filling  composed  of  two  or 
more  distinct  snbstances  introdneed  into  the  cavity  separately. 

Objects  of  a  Combination.  The  object  of  combining  various  ma- 
terials in  the  filling  of  a  tooth's  cavity  is  to  secure  a  perfect  fill- 
ing, one  possessed  of  all  vii-tues,  and  no  faults.  Many  such  com- 
binations of  material  meet  this  demand  in  a  large  measure  by 
bringing  into  service  the  strong  features  of  each  material,  and  at 
the  same  time  nullifying  the  faults  of  all  material  entering  into  the 
construction. 

Since  dentistry  has  been  raised  to  the  dignity  of  a  science  there 
has  been  a  diligent  search  to  discover  a  filling  material  which  pos- 
sesses the  virtues  of  all  and  the  faults  of  none  in  present  use.  At 
the  present  time  this  is  more  nearly  reached  by  the  various  com- 
binations possible  with  the  usual  distinct  materials.  If  perchance 
the  ideal  filling  is  ever  produced,  dentistry  will  at  once  become 
much  simplified  as  to  methods  of  procedure. 

Single  Materials  Used  as  a  Filling.  There  are  only  two  filling 
materials  now  in  use  which  are  used  in  their  pure  state,  pure  gold 
and  pure  tin,  and  there  are  many  instances  where  these  combined 
Avith  each  other  or  Avith  other  materials,  Avill  produce  better  results 
than  Avhen  used  alone. 

Gold  and  Tin  Combination.  This  condiination  is  of  service  in 
large  cavities  of  Class  Two  which  are  subgingival  and  in  large 
oeclu.sal  cavities  in  molars,  where  the  i)ulpal  wall  is  deep  and 
rounded.  In  this  combination  the  tin  should  be  placed  in  the  cav- 
ity first  and  thoroughly  condensed,  and  the  filling  com])leted  with 
cohesive  gold. 

In  Class  Two  the  tin  should  cover  the  gingival  Avall  at  least  one 
millimeter  deep  and  be  condensed  to  ])la('o  with  Uie  mali'ix  in 
position. 

Benefits  derived.  Dcniinc  upon  wliich  has  been  built  a  thor- 
oughly condensed  tin  filliny-  docs  not  readily  decay.  Bv  com- 
pleting the  filling  A\ith  gold  the  discoloi-ation  of  tooth  substance 
is  avoided  and  the  gold  will  bettci-  i-esist  the  force  of  mastication. 

Gold  and  Cement.  The  ol^jcct  of  this  coinhination  is  to  ]U'oduce 
a  filling  tliat  is  adhesive,  will  ])rotect  A\cal<  ANalis,  and  resist  the 
lluids  of  the  mouth  and  the  force  of  mastication. 

](]9 


170  OPERATIVE   DENTISTRY 

Two  Methods  of  Combining'.  There  are  two  methods  of  produc- 
ing this  combination.  One  is  to  cast  the  filling  and  lay  it  into  the 
cement-covered  cavity,  which  is  the  inlay  method.  The  other  is 
to  build  cohesive  gold  into  a  thin  mix  of  soft  cement  with  which 
the  walls  of  the  cavity  have  been  coated.  The  essential  feature  of 
both  is  that  the  cement  be  completely  covered  to  protect  it  from 
dissolution  by  external  agencies,  as  the  fluids  of  the  mouth  and  the 
effects  of  wear. 

When  Indicated.  The  inlay  combination  is  indicated  in  large 
cavities  of  easy  access.  The  built-in  method  of  combination  is  in- 
dicated in  small  cavities  of  more  difficult  access,  and  where  cor- 
rect cavity  formation  is  impossible  or  ill-advised.  When  using 
this  method  convenience  angles  may  be  omitted. 

Gold  and  Platinum.  This  combination  adds  to  the  many  virtues 
of  cohesive  gold  fillings  by  increasing  the  resistance  of  the  filling 
to  the  wear  of  mastication.  The  pure  gold  is  first  used  as  it  is  capa- 
ble of  more  perfect  adaptation  to  the  walls,  all  of  which  should 
be  covered  before  taking  up  the  platinized  gold.  The  contour  por- 
tion should  be  made  of  the  alloy.  This  alloy  comes  from  the  sup- 
ply house  in  sheets  which  appear  to  be  pure  gold  except  that  the 
color  is  a  little  lighter.  This  foil  comes  in  three  numbers,  1,  2  and 
3,  the  No.  2  being  preferable  for  most  cases. 

The  rules  for  condensation  are  just  the  same  as  for  pure  gold, 
only  the  observance  of  each  specific  rule  giVen  on  that  subject  is 
more  emphatically  demanded  here,  and  when  strictly  followed  the 
alloy  will  prove  as  easily  handled. 

Cohesive  Gold  and  Non-Cohesive  Gold  Combined.  By  this  com- 
bination much  time  is  saved  as  the  non-cohesive  gold  may  be  in- 
troduced in  greater  masses  than  the  cohesive.  Also  the  soft  gold 
is  more  easily  adapted  to  the  walls  than  cohesive. 

The  cohesive  gold  is  used  to  finish  the  contour  as  it  will  better 
resist  the  torsion  strain  and  the  effects  of  abrasion.  Before  the 
introduction  of  cohesive  gold  all  gold  fillings  were  non-cohesive, 
but  since  the  introduction  of  the  former  the  art  of  filling  teeth 
well  with  soft  gold  has  rapidly  declined,  so  that  the  making  of  an 
entirely  non-cohesive  gold  filling  is  now  the  exception. 

Cement  and  Amalgam.  Results  similar  to  what  might  be  termed 
an  amalgam  inlay  are  produced  by  coating  the  prepared  cavity  with 
cement,  and  immediately  burnishing  into  this  fresh  cement,  a  por- 
tion of  the   amalgam.     The   enamel  margins   are   rendered   clean 


COMBINATION    FILLINGS 


171 


again  by  freshly  cutting  them  with  a  chisel  for  their  entire  outline 
and  the  amalgam  filling  immediately  finished  in  the  usual  way. 

The  Benefits.  This  combination  produces  a  filling  with  the  vir- 
tues of  an  amalgam  to  which  is  added  the  adhesion  of  the  cement 
and  the  protection  of  cavity  wall  from  fracture  and  discoloration 

When  Indicated.  This  is  indicated  in  most  large  cavities  to  be 
filled  with  amalgam,  where  the  walls  are  weak  and  thin  and  in 
cavities  where  insufficient  retentive  form  is  secured. 

Cement  and  Porcelain.  Cement  is  combined  with  porcelain  in 
the  filhng  of  teeth  for  the  purpose  of  making  the  filling  adhere. 
The  porcelain  protects  the  cement  from  dissolution. 

Silicate  Cement  and  Fused  Porcelain.     Fused  porcelain    inlavs 


g^o^^^-^iJ:^.^°^  -- -f  -^,  d^-^^!iii!j^i^\^-X  ^n  [:isr 


»^  16-    ■•"". — \-oirioinaiion 
ready  to  receive  the  silicate 

may  be  set  with  some  of  the  silicate  cements  to  great  advantage. 
The  silicate  filling  materials  which  are  at  their  best  when  mixed 
thin  enough  to  be  adhesive  are  those  which  can  be  used  as  a  ce- 
ment. In  fact  some  operators  are  using  these  materials  for  setting 
the  gold  inhiy  with  seemingly  good  results. 

Silicate  and  Gold.  Silicate  may  be  used  to  face  the  gold  fillino- 
lor  esthetic  reasons.  In  filling  Class  Four  cavities  with  the  gold 
inlay,  by  either  one  of  the  four  phins,  the  wax  may  be  cut  out  of 
the  pattern  so  as  to  present  a  labial  surface  almost  entirely  of 
silicate.  After  these  two  materials  are  combined  in  this  class  of 
cavity,  care  should  be  taken  that  the  incisal  edge  is  of  gold  and 


172 


OPERATIVE   DENTISTRY 


particularly  that  the  cavo-surface  angle  on  the  incisal  outline  is 
protected  by  one-half  of  a  millimeter  to  a  millimeter  of  the  cast 
gold.  The  cast  should  be  made  and  set  with  oxyphosphate  of 
zinc  cement.  At  a  subsequent  setting  the  silicate  face  may  be  built 
in.  A  similar  effect  is  produced  with  the  bicuspids  and  molars,  in 
crown  work.  The  gold  crown  is  made  in  the  usual  way  and  set. 
A  carborundum  stone  is  applied  to  the  buccal  surface  and  ground 
away  and  a  sufficient  amount  of  cement  cut  out  to  make  room  for 
the  building  in  of  the  silicate.  Before  building  in  the  silicate  it  is 
best  to  coat  the  cement  which  is  exposed  within  the  crown  with  a 
thin  application  of  copal-ether  varnish. 

Silicate  and  Amalgam.    Many  large  contour  amalgam  fillings  on 
the  mesial  surfaces   of  bicuspids   and  molars  i)articularly   in  the 


Fig.    107.  Fig-    108. 

Fig.   107. — Amalgam  in  position   ready  to  receive  a  partial  facing  of  silicate. 

Pig  108— This  represents  the  amalgam  filling  shown  in  Fig.  107  with  the  silicate  facing 
built  in.  The  dotted  line  shows  the  outline  of  the  silicate  with  that  portion  marked  x,  repre- 
senting the  silicate. 

superior  teeth  are  unsightly.  A  very  pleasing  effect  is  produced 
l)y  cutting  away  the  mesio-buccal  contour  of  amalgam,  either  in 
new  or  old  fillings,  and  in  the  resulting  cavity,  build  silicate.  The 
silicate  will  not  discolor  when  thus  applied  to  the  amalgam.  How- 
ever, each  individual  case  seems  to  require  a  different  shade  and 
to  get  it  right  a  trial  mix  should  be  made  before  deciding  on  the 
combination  of  powder  to  produce  the  desired  shade. 

Silicate  as  Applied  to  Prosthetic  Work.  It  is  not  Avithin  the 
scope  of  this  book  to  deal  with  prosthetic  procedures.  However, 
it  is  well  to  call  attention  to  the  fact  that  this  material  is  used  to 


COMBINATION    FILLINGS  173 

advantage  in  the  facing-  of  crowns,  the  fitting  of  gingival  ends  of 
porcelain  pin  crowns  to  the  root,  and  its  application  to  many 
places  in  pieces  of  bridge  work.  It  is  also  useful  in  the  facing  of 
Ijartial  and  full  removable  dentures  in  a  color  to  imitate  the 
natural  gum  tissues. 

There  are  many  other  combinations  which  are  made  and  used 
to  advantage  in  tooth  salvage.  It  is  improbable  that  the  perfect 
filling  material  will  ever  be  produced  as  the  demands  are  so  varied 
in  different  mouths,  and  in  different  localities  in  the  same  mouth. 

"We  are  more  nearly  able  to  meet  all  of  those  varying  conditions 
by  a  wise  selection  of  the  materials  to  be  used  in  each  case  and  a 
judicious  combination  will  go  far  to  produce  the  perfect  filling  for 
each  individual  cavity  as  presented. 


PART  III 

CHAPTEK  XXIX. 

EXAMINATION  OF  THE  MOUTH  LOOKING  TO 
DENTAL  SERVICES 

The  First  Duty  of  a  dentist  to  one  presenting  himself  for  dental 
services  is  to  comply  with  the  patient's  request,  which  is  generally 
to  examine  a  special  tooth  or  a  diseased  condition  of  which  the 
patient  is  aware.  If  the  patient  does  not  make  such  a  special  re- 
quest it  is  well  to  ask  some  form  of  a  leading  question  as  to  the 
reason  of  the  call.  This  fact  elicited,  all  else  should  be  ignored 
until  the  object  of  the  first  visit  has  been  accomplished. 

A  Light  Hand  and  Slow  Movements  are  very  essential  for  the  first 
few  moments,  especially  at  the  first  meeting  of  patient  and  dentist, 
as  first  impressions  are  often  lasting  and  if  the  stranger  is  ap- 
proached in  a  careless  manner  he  may  get  ideas  of  undue  rough- 
ness, many  times  unfounded,  yet,  nevertheless,  lasting  with  the 
nervous  patient. 

The  Washing"  of  the  Hands  in  the  patient's  presence  or  in  run- 
ning water  within  hearing  of  the  patient  should  be  universally 
practiced  no  matter  if  the  operator  knows  his  hands  to  be  already 
scrupulously  clean,  as  it  assures  the  patient  that  the  operator  has 
a  regard  for  at  least  the  simpler  forms  of  cleanliness. 

The  Linen  Upon  the  Chair  should  be  inviting  and  unsoiled.  If 
convenient,  it  is  well  that  the  patient  see  that  which  is  already  on 
the  chair  changed  for  fresh. 

Few  Instruments  should  be  in  sight,  as  they  serve  to  remind  the 
patient  of  former  experiences  not  always  pleasant. 

After  the  First  Requests  of  the  patient  have  been  complied  with 
it  is  well  to  take  a  rather  general  survey  of  the  mouth  before  an- 
swering many  questions  regarding  the  advice  to  the  patient  as  to 
future  procedures.  The  operator  should  note  in  this  "bird's-eye 
view,"  as  it  Avere,  the  probable  care  that  is  being  bestowed  upon 
the  teeth  and  mouth  in  a  prophylactic  way.  Also  the  health  of  the 
soft  tissues,  the  number  of  extracted  teeth,  the  presence  of  den- 
tures and  amount  of  dental  Avork  previously  done,  noting  its  qual- 
ity and  probable  age,  as  well  as  the  number  of  badly  decayed  teeth 
yet  unfilled.     He  should  note  the  health  of  the  patient,  probable 

174 


EXAMINATION    OF    MOUTH    LOOKING    TO    DENTAL    SERVICES  175 

age  and  habits.  All  this  can  be  done  at  a  glance  and  in  a  few 
second's  time,  Avhen  the  operator  will  be  much  better  qualified  to 
advise  the  patient  as  to  Avhat  is  best  to  do  in  a  special  case. 

If  the  Patient  Is  in  Pain  its  alleviation  is  of  first  importance  and 
should  receive  immediate  attention.  It  may  require  the  applica- 
tion of  medicinal  remedies,  or  some  mechanical  procedure  or  even 
the  extraction  of  a  tooth,  but,  whatever  it  may  be,  it  must  be  done 
at  once  as  the  patient  is  in  no  mood  to  receive  sage  advice  about 
the  future  when  he  is  at  present  in  pain. 

Early  in  the  Examination  Sitting-  the  patient  should  be  advised 
of  the  necessity  of  a  prophylactic  treatment  provided  the  teeth 
and  mouth  are  not  scrupulously  clean,  which  is  seldom  the  case, 
nnless  the  patient  has  recently  visited  the  dentist  for  that  purpose. 

This  Is  Second  Only  to  the  relief  of  pain  and  it  is  manifestly  the 
dentist's  duty  to  attend  to  prophylaxis  before  proceeding  to  the 
making  of  fillings. 

A  Careful  Examination  should  be  suggested,  folloAving  the  hasty 
inspection,  and,  if  advised  to  do  so  by  the  patient,  the  dentist  may 
then  proceed  to  search  all  surfaces  for  the  various  classes  of  decay, 
not  forgetting  the  vulnerable  points  about  Avork  previously  placed, 
as  the  margins  of  fillings  and  about  the  bands  of  crowns. 

The  Instruments  Needed  are,  a  clear,  uninjured  mouth  mirror,  a 
sharp  pointed  instrument  called  an  explorer ,  cotton  pliers  and 
small  balls  of  absorbent  cotton,  waxed  floss  silk,  chip  blower  and 
mechanical  separator.     A  small  electric  mouth  lamp  is  also  of  value. 

The  Use  of  the  Mouth  Mirror  is  to  see  therein  the  image  of  sur- 
faces and  locations  where  direct  vision  is  impei-fect  or  impossible 
and  to  flood  the  point  being  examined  with  an  abundance  of  light. 
Many  cavities  existing  in  the  proximal  spaces  are  not  noticed  until 
strong  rays  of  light  from  a  different  angle  than  the  line  of  vision 
of  the  examiner  have  been  dii-ected  against  them. 

The  Use  of  the  Explorer  is  to  note  the  extent  of  decalcification 
at  suspected  points  and  the  inspection  ol'  pits  and  grooves  for 
faults  in  enamel.  This  instrument  should  be  in  the  shape  of  an 
elongated  cork  screw  turn,  that  the  more  inaccessible  points  may 
be  reached.  A  light  hand  in  i1s  use  is  iin])('fative  as  the  dentist 
is  not  excu.sed  for  breaking  (lov>n  tooth  substances  or  for  causing 
much  pain  in  any  of  the  processes  af  examination. 

Absorbent  Cotton  in  the  pliers  is  used  to  take  up  the  moisture  in 
cavities  of  considerable  si/e  and   wliosc  depth  ([ucstions  pi'oxiniity 


176  OPERATIVE  DENTISTRY 

to  the  pulp ;  also  sensitive  surfaces  suspected  in  shallow  cavities, 
particularly  those  in  the  gingival  third.  The  cotton  balls  should 
not  be  too  large  and  rather  tighth^  rolled. 

Waxed  Floss  Silk  is  used  to  examine  the  proximal  space  where 
the  reflection  of  light  does  not  make  diagnosis  positive.  It  cleans 
the  surfaces  of  debris  and  food  particles,  giving  a  deeper  insight 
from  the  embrasure.  When  surfaces  are  roughened  or  cupped  from 
incipient  caries,  it  will  show  by  the  catching  or  cutting  of  the  fibers 
of  the  thread ;  if  the  surfaces  still  retain  their  normal  polish  the 
thread  will  pass  uninjured. 

The  Chip  Blower  is  a  small  hand  bellows  for  the  expulsion  of  air 
and  is  used  in  examination  of  the  teeth  to  blow  away  and  evaporate 
the  moisture  from  points  where  it  is  held  by  capillary  attraction, 
giving,  thereby,  a  better  view  and  a  more  correct  idea  as  to  the 
color  present,  which  is  a  strong  factor  in  a  diagnosis  of  conditions. 

The  Mechanical  Separator  will  sometimes  be  of  service  to  gain 
a  little  added  space  for  the  inspection  of  contacting  surfaces. 

The  Use  of  the  Electric  Lamp  on  the  lingual  side  of  the  teeth  has 
many  advantages  and  is  a  speedy  and  sure  way  of  detecting  any  of 
the  stages  of  caries  in  the  proximal  spaces,  the  vitality  of  a  tooth's 
pulp  as  well  as  abnormal  conditions  about  the  alveolar  wall  and  the 
presence  of  pus  and  inflammatory  changes  in  the  maxillary  sinus. 

When  the  Examination  Is  Completed  the  patient  should  be  ad- 
vised of  the  true  condition  of  his  mouth,  including  the  indicated 
treatment  of  both  hard  and  soft  tissues.  If  the  patient  indicates 
a  desire  to  have  the  services  rendered  as  outlined  by  the  dentist  it 
is  entirely  good  business,  and  by  no  means  unprofessional,  to  ap- 
prise the  patient  of  the  probable  cost  of  the  work  as  planned  when 
it  can  be  approximately  estimated,  unless  the  patient  is  a  frequent 
visitor  and  familiar  with  the -charges  expected  from  the  dentist  con- 
sulted. 


CHAPTER  XXX. 
THE  ALLEVIATION  OF  DENTAL  PAINS. 

The  First  Duty  of  the  Dentist  is  to  relieve  suffering,  and  as  in 
many  instances  this  is  the  reason  for  the  first  call  of  the  patient  it 
is  most  essential  that  the  relief  sought  is  obtained.  Many  times  the 
relieving  of  a  paroxysm  of  pain  by  the  dentist  has  made  a  lifelong 
friend  and  patient. 

The  Diagnosis  is  a  most  vital  point  and  the  battle  is  half  won 
when  tliis  is  correctly  made. 

Pay  Strict  Attention  to  What  the  Patient  Has  to  Say  as  he  is 
quite  sure  to  give  you  his  symptoms  in  the  order  of  their  prominence 
and  it  is  generally  the  prominent  symptoms  that  are  pathognomonic. 

After  the  Patient  Has  Given  the  Most  Aggravated  Symptoms, 
make  an  examination  of  the  afflicted  part  of  the  mouth  to  verify  the 
statements  made.  If  all  is  not  clear  quiz  him  more  specifically.  Do 
not  jump  at  conclusions.  The  patient  is  generally  right  as  to  symp- 
toms but  frequently  wrong  as  to  location  and  cause.  These  last  are 
the  points  the  dentist  must  decide,  as  well  as  upon  the  treatment  for 
relief. 

There  Are  Two  Divisions  of  Dental  Pains,  those  arising  from 
lesions  of  the  tooth  pulp,  and  those  arising  from  degenerative  changes 
in  the  sub-dental  tissues,  which  are  generally  the  sequela  of  the  same 
destructive  processes  in  the  pulp.  They  may  follow  the  pulp  troubles 
or  occur  simultaneously  with  them. 

Pulp  Lesions.  Symptoms  are  sensitiveness  to  thermal  changes. 
The  tooth  is  not  necessarily  sore  to  percussion.  Pain  is  increased 
or  induced  when  assuming  a  recumbent  position.  The  presence  of 
foreign  substances  in  the  tooth  cavity  cause  pain  especially  when 
pressed  against  the  walls  of  the  cavity.  Pain  comes  in  paroxysms 
with  a  tendency  to  intermittence.  Patient  may  complain  of  ''jump- 
ing toothache."  These  symptoms  may  all  be  present  in  the  same 
case  or  only  one  at  a  time  in  the  series  of  changes  that  take  place 
ill  M  pulp  from  the  initial  affection  to  its  death. 

The  Treatment  for  Speedy  Relief  is  varied  according  to  the  most 
jtroiniiicnt  syiii[)1()iiis,  ;is  llicsc  are  the  indications  of  the  stage  of  dis- 
sf)lutioii. 

If  Cold  Air  or  Water  Causes  Pain  of  a  quick,  sharp,  shooting  na- 
ture. coiiK's  on  suddenly  and  passes  off  immediately  upon  the  tooth 
regaininjr  the  body  ternixTalure,  the  }>ulp  is  in  the  stages  of  active 

177 


178  OPERATIVE   DENTISTRY 

hyperemia,  which  is  the  initial  stage  of  a  destructive  disease,  and 
will  respond  immediately  to  the  application  of  anodyne  and  effectual 
protection  from  air  and  fluids,  which  is  accomplished  by  stopping 
the  cavity  with  a  non-conductor,  generally  cotton,  or  temporary  stop- 
ping, or  an  application  of  phenol. 

If  Warm  Fluids  Cause  or  Intensify  the  Pain  and  the  application 
of  cold  relieves  the  pain  temporarily,  the  pulp  will  be  found  to  be 
well  advanced  in  the  stages  of  dissolution,  some  portion  of  which 
has  been  resolved  into  the  end  products.  Gaseous  substances  oc- 
cupy portions  of  the  pulp  cavity,  which  is  closed  over  the  entire 
coronal  portion  by  a  layer  of  dentine,  a  filling  or  a  plug  of  foreign 
substance.  These  gases  are  expanded  by  the  elevation  of  the  tem- 
perature, causing  increased  pressure  upon  the  remaining  vital  por- 
tions of  the  pulp  and  intense  pain  results,  which  is  further  aug- 
mented, many  times,  by  the  pulsations  of  the  heart.  The  pulsating 
symptom  in  this  instance  indicates  that  quite  a  portion  of  the  pulp 
is  yet  vital. 

The  Treatment  for  Relief  in  This  Case,  Avhich  is  called  closed 
putrescence,  is  the  removal  of  the  obstruction  for  the  escape  of  the 
gas.  This  involves  opening  into  the  pulp  chamber  through  the  route 
of  the  least  obstruction  or  injury  to  the  tooth.  Necrotic  portions  of 
the  pulp  should  be  removed,  disinfectants  and  anodynes  applied  and 
devitalization  of  the  remaining  vital  portion  effected. 

If  Moderately  Warm  Fluids  Cause  Pain  as  well  as  cold  the  pulp 
is  in  the  first  stages  of  passive  hyperemia  or  congestion.  This  con- 
dition is  generally  soon  followed  by  the  symptom  of  being  more  pain- 
ful upon  the  patient's  lying  down  and  the  throbbing  pains  setting 
in,  and  many  times  patients  will  say,  "I  have  the  jumping  tooth- 
ache ; "  or,  "  It  began  last  evening  about  fifteen  minutes  after  I  went 
to  bed." 

Treatment  of  Passive  Hyperemia  Pulp  for  relief  is  sterilization 
of  immediate  surrounding  tissue  at  the  tooth's  cavity  and  the  ap- 
plication of  sedatives  and  anodynes.  If  the  pulp  can  be  bled  with 
causing  but  slight  pain  it  is  beneficial ;  then  proceed  to  devitalization. 

The  Painting  of  the  Gum  with  a  revulsive  is  of  service,  especially 
if  the  pericementum  is  taking  on  the  stages  of  inflammation  indi- 
cated by  slight  soreness  to  percussion. 

If  the  Presence  of  a  Foreign  Substance  in  a  cavity  causes  pain  it 
may  be  an  exposed  pulp  which  is  not  very  highly  organized,  or  hyper- 
sensitive dentine  covered  with  a  layer  of  leathery  decay. 

The  Treatment  Is  the  Removal  of  the  offending  object  and  the 
prevention  of  its  recurrence  by  temporary  or  permanent  stopping. 


ALLEVIATION    OF    DENTAL    PAINS  179 

Pericemental  Diseases  Causing  Pain  have  for  their  most  path- 
ognomonic symptom  the  soreness  to  percussion,  as  shown  by  gently 
tapping  on  the  occlusal  surface  of  the  tooth  with  a  steel  instru- 
ment. Slight  swelling  of  the  pericementum  causes  the  tooth  to  ap- 
pear to  the  patient  as  much  elongated  and  the  patient  will  generally 
make  such  remarks  as  these,  "I  have  a  sore  tooth;"  "It  hurts  to 
close  my  teeth;"  "My  tooth  is  too  long,"  etc. 

If  the  pulp  is  entirely  dead,  and  removed,  or  there  is  not  a  ease 
of  enclosed  putrescence,  thermal  changes  will  have  no  effect,  except 
in  rare  eases  warmth  applied  to  the  parts  will  give  a  slight  sense  of 
relief. 

Treatment  for  the  Relief  of  Pericemental  Pains  is  the  thorough 
and  complete  removal  of  the  cause,  generally  consisting  of  necrotic 
pulp  tissue,  and  infectious  matter  in  the  pulp  chamber.  This  should 
be  thoroughly  removed  by  mechanical  means,  assisted  by  the  use  of 
chemicals,  and  the  entire  chamber  from  crown  to  apex  rendered 
aseptic  as  soon  as  possible. 

If  Pus  Has  Formed  at  the  apical  space  and  flows  freely  down  the 
root  canal  temporary  relief  is  most  certain  to  follow  if  the  case  is 
allowed  to  remain  open  for  twenty-four  or  forty-eight  hours  for 
free  drainage,  when  fiirtlior  treatment  may  be  proceeded  with. 

Acute  Alveolar  Abscesses  should  be  opened  externally,  as  soon 
as  the  presence  of  pus  can  be  diagnosed,  this  to  be  done  external  to 
the  alveolar  wall  and  is  least  painfully  done  by  freezing  the  tissues 
to  be  punctured. 

Abscesses  Are  Assisted  to  the  Surface  by  painting  the  mucous 
membrane  over  the  diseased  portion  Avith  aconite  and  iodine.  In  no 
case  should  such  an  abscess,  no  matter  what  its  size,  be  lanced  through 
the  external  surface  of  the  face  as  all  are  easily  reached  from  within 
the  mouth. 


CHAPTER  XXXI. 
PEOPHYLACTIC  TREATMENT  OF  THE  MOUTH. 

The  Importance  of  Prophylactic  Treatment  early  in  a  series  of 
visits  to  a  dentist  and  at  stated  periods  thereafter,  is  second  only 
to  the  relief  of  pain,  the  neglect  of  which  jeopardizes  the  remain- 
ing tooth  structures,  the  permanency  of  attempts  to  check  the 
ravages  of  caries  and  disease,  as  well  as  the  reputation  of  the  op- 
erator's skill. 

Unhygienic  Conditions  About  the  Teeth  are  the  sole,  immediate 
and  exciting  cause  of  primary  or  secondary  decay  of  the  teeth, 
and  many  an  operator  of  exceptional  skill  as  to  the  making  of 
fillings  has  failed  from  a  disregard  of  these  conditions.  As  much 
of  the  success  of  dental  operations  depends  upon  the  care  of  the 
mouth  by  both  dentist  and  patient  in  the  w^ay  of  prophylaxis,  as 
upon  the  skill  of  the  dentist  as  an  operator.  The  making  of  a  fill- 
ing is  but  the  repair  of  an  injury  and  is  only  a  temporary  check 
to  the  progress  of  destruction,  if  the  primary  cause  of  dissolution 
is  to  remain  operative. 

The  Sub-Dental  Tissues  are  also  diseased  by  a  lack  of  prophy- 
laxis to  the  extent,  many  times,  of  their  entire  loss,  so  that  the 
teeth,  themselves,  are  loosened  and  lost,  through  a  lack  of  struc- 
tures to  support  them,  w^hile  the  teeth  so  lost  are  many  times  yet 
undecayed,  and,  in  the  present-day  advancement  of  dentistry,  ex- 
perienced operators  are  forced  to  consign  more  teeth  to  the  for- 
ceps from  the  result  of  diseased  conditions  in  the  tissues  surround- 
ing them  than  from  decay  of  the  teeth,  themselves.  If  this  be 
true  the  dentist  cannot  ignore  the  importance  of  combating  the 
agencies  which  bring  it  about. 

Preventive  Dentistry  has  the  same  great  field  of  usefulness  as 
has  "preventive  medicine"  in  the  practice  of  medicine  and  the 
dentist  who  masters  this  phase  of  the  science  of  dentistry  has  gone 
a  long  way  towards  success,  and  many  defects  in  manipulation, 
ability  and  ideals  in  conditions  about  tooth  repair  impossible  of  at- 
tainment, will  stand  the  test  of  time  if  only  hygienic  conditions 
are  attained  and  maintained. 

The  Kinds  of  Deposits  Upon  the  Teeth  are  generally  classified 
as  salivary  calculus,  serumal  calculus,   green  stain  and  sordes. 

The  first  two  named  are  enemies  to  tissue  about  the  teeth,  while 

180 


PROPHYLACTIC    TREATMENT    OF    THE    MOUTH  181 

the  last   two  are  responsible  for  most   of  the  destruction  of  the 
hard  dental  tissues  l)y  caries. 

Composition  of  Salivary  Calculus.  Mixed  saliva  contains  in 
man  an  average  of  al)out  0.5  per  cent  solids.  The  calculus  is  pre- 
cipitated into  the  mouth  in  a  form  of  a  finely  divided  calco- 
globulin,  Avhich  collects  in  masses  upon  any  stationary  object, 
close  to  the  mouth  of  the  gland  ducts.  The  fresh  deposit  is  very 
soft  and  greasy  to  feel  when  first  deposited,  but  within  twenty- 
four  hours  it  begins  to  harden  and  increases  in  hardness  up  to  the 
time  of  thirty  or  sixty  days,  when  it  has  generally  attained  its  full 
hardness  and  will  break  away  from  the  stationary  ol)ject  in  masses 
shoAving  distinct  lines  of  fracture. 

Lime  Salts  Held  in  Solution.  Calcium  phosphate  and  magnesium 
phosphate  are  held  in  solution  in  the  saliva,  made  possible  by  the 
presence  of  a  little  carbon  dioxide. 

Reasons  for  Precipitation.  When  the  saliva  is  discharged  into 
the  mouth  it  is  released  from  the  normal  blood  pressure  and  some 
of  the  carbon  dioxide  escapes  which  allows  the  calcium  salts  to  be 
precipitated.  The  lactic  acid  Avhieh  is  continually  formed  in  the 
mouth  converts  the  mucus  into  a  curd  in  which  the  calcium  salts 
are  entangled  to  harden  into  salivary  calculus.  This  process  is  as- 
sisted by  the  presence  of  the  oxygen  taken  into  the  mouth  with  the 
breath,  Avhich  facilitates  the  liberation  of  the  carbon  dioxide,  in 
the  process  of  oxidization. 

Time  of  Deposits.  It  Avould  seem  from  the  experiments  of  Dr. 
Black  that  the  deposits  of  salivary  calculus  are  paroxysmal  and 
also  that  these  periods  of  rapid  deposit  follow  the  ingestion  of 
heavy  meals.  He  thinks  that  these  periods  of  excessive  deposits 
come  at  a  time  Avhen  the  blood  is  overcharged  with  food  pabulum. 

Kind  of  Food.  It  (Iocs  not  seem  from  his  experiments  that  the 
kind  of  food  has  very  much  to  do  with  these  deposits.  The  more 
easily  a  food  is  digested,  the  more  quickly  folh)wing  the  meal  will 
the.se  deposits  appear. 

Habits  of  Patient.  Tt  Avould  seem  that  the  habits  of  the  patient 
have  little  to  d(j  in  influencing  the  amount  of  these  deposits. 
However  those  Avho  live  a  life  of  physical  exertion,  which  favors 
the  using  of  heavy  meals  have  a  greater  tendency  to  deposits  of 
tartar  than  those  Avhoso  vocation  Avould  cause  them  lo  eat  lightly. 

Mouths  Most  Subject  to  the  Deposit.  From  our  ])reseiit  under- 
standing of  this  subject  it  would  seem  that  the  mouths  most  sub- 
ject to  1h('  dcposil  of  s;iliv;ii'\'  c;ilculus  ai'o  those  individuals. 


182  OPERATIVE   DENTISTRY 

First,  who  from  constitutional  reasons  have  a  tendency  to  an 
abundance  of  carbon  dioxide  in  the  excretions  and  secretions. 
This  condition  may  be  brought  about  by  great  physical  or  mental 
activity  or  v^here  the  skin,  kidneys  or  lungs,  or  all,  are  not  per- 
forming their  full  functions.  These  are  the  principal  eliminaters 
of  carbon  dioxide.  Such  individuals  are  very  liable  to  be  troubled 
with  precipitation  M^ithin  the  gland  and  ducts,  through  v^hich  their 
secretions  are  expelled,  resulting  in  cystic,  glandular,  biliary  or 
renal  calculi. 

Second,  those  individuals  who  either  occasionally  or  habitually 
engorge  heavy  meals,  wherein  the  quantity  of  such  meals  is  greater 
than  that  needed  for  growth  or  maintenance. 

Third,  in  mouths  wherein  the  amount  of  lactic  acid  is  more  than 
normal. 

Fourtli,  in  the  mouths  of  public  speakers  and  mouth  breathers, 
whether  awake  or  during  sleep.  The  great  amount  of  oxygen  com- 
ing in  contact  with  the  saliva  assists  in  the  rapid  liberation  of  the 
carbon  dioxide  and  consequent  rapid  precipitation  of  the  calcium 
salts. 

Prevention  of  Salivary  Deposits.  It  would  seem  that  salivary 
deposits  can  largely  be  prevented  by  stimulating  the  circulation; 
stimulating  the  elimination  of  carbon  dioxide  from  the  body; 
checking  mouth  breathing  as  much  as  possible,  correcting  over- 
acidity  of  the  mouth,  limiting  the  amount  of  food  taken  into  the 
stomach  at  each  meal  by  more  nearly  equalizing  the  three  daily 
meals  to  the  needs  of  the  body.  Also  by  so  highly  polishing  the 
e^urfaces  of  the  teeth  upon  which  the  deposit  is  precipitated,  as  to 
facilitate  the  mechanical  removal  of  the  fresh  deposits.  Last  but 
not  least,  so  instructing  the  patients  in  the  mechanical  features  of 
the  care  of  their  teeth  that  insofar  as  possible  all  fresh  deposits 
are  removed  before  hardening  takes  place. 

Serumal  Calculus  is  a  calcic  precipitate  from  the  blood.  The 
salts  in  solution  in  the  blood  as  well  as  the  stability  of  suspension 
depends  materially  upon  the  presence  of  a  normal  amount  of  car- 
bon dioxide. 

Serumal  Calculus  Is  Deposited  beneath  the  gum  tissue  wherein 
there  is  a  passive  hyperemic  condition  or  congestion.  Here  we 
have  excessive  tissue  waste,  lessened  alkalinity  of  the  blood,  a  lib- 
eration of  the  carbon  dioxide  and  consequent  precipitation  of  the 
inorganic  salts.     By  the  recession  of  the  gum  after  the  formation 


PROPHYLACTIC    TREATMENT    OF    THE    MOUTH  183 

of  the  serumal  form  of  calculus,  it  may  be  exposed  to  view,  or 
mixed  Avith  the  mass  of  salivary  calculus. 

Serumal  Calculus  in  Appearance  is  of  a  much  darker  color  than 
salivary  of  a  harder  constituency,  and  generally  adheres  to  the 
surface  of  the  tooth  more  tenaciously. 

Serumal  Calculus  Is  Also  Found  on  unexposed  portions  of  roots 
of  teeth  Avhicli  approximate  inflammatory  exudates,  or,  are  bathed 
in  escaping  blood  plasma  associated  with  chronic  conditions  of  the 
apical  space.  It  also  appears  in  other  portions  of  the  body  as 
about  the  joints  subjected  to  chronic  inflammations  as  well  as  in 
the  glands  continually  gorged  with  blood. 

The  Bulk  of  Serumal  Calculus  is  comparatively  small,  owing  to 
its  formation  in  restricted  spaces  and  is  generally  found  in  small 
nodules,  narroAv  bands  and  thin  scales,  not  always  easy  of  detec- 
tion or  removal. 

Stains  Upon  the  Teeth  are  of  varying  degrees  of  shade  in  several 
colors  and  from  co.smetic  reasons  stand  for  immediate  removal 
when  detected.  However  the  green  stain  found  upon  teeth  is  so 
closely  connected  with  the  first  stages  of  caries  on  surfaces  so  af- 
fected that  it  deserves  special  consideration. 

Green  Stain  Is  Generally  Confined  to  the  labial  surfaces  and 
particularly  the  gingival  third  of  the  anterior  teeth.  It  is  most 
frequently  found  upon  the  teeth  of  children  and  may  be  seen 
either  upon  the  temporary  or  permanent  teeth.  When  it  persists 
for  a  considerable  time  upon  these  surfaces  of  the  permanent 
teeth  the  enamel  will  be  found  to  be  etched  by  a  dissolution  of  the 
cemental  substance  evidenced  by  the  whitened  surface. 

The  Color  Is  Due  to  the  bacteria  present. 

The  Injury  to  Tooth  Substance  is  due  to  the  acid  which  these 
bacteria  produce. 

The  Reason  for  Their  Presence  is  the  favora])le  place  for  lodg- 
ment affoi'ded  by  the  pei'sistence  of  the  cuticula  dentis. 

Sordes  Consists  of  a  mixture  of  food,  epithelial  matter  and 
micro-organisms  collected  upon  the  teeth. 

Neglect  in  the  Removal  of  Sordes  results  in  tooth  caries,  partic- 
ularly in  localities  habitually  so  unclean. 

The  Removal  of  Salivary  Calculus  is  accomplished  by  two  prin- 
cipal plans,  the  push-cut  method  and  the  draw-cut  method,  each 
with  its  advantages. 

By  the  Push-Cut  Method  the  blade  of  the  scaler,  which  has  a 
blunt  chisel  edge,  is  forced  between  the  calculus  and  enamel  trav- 


184  OPERATIVE   DENTISTRY 

eling  in  the  direction  of  the  root.  In  its  use  the  principal  danger 
is  the  slipping  of  the  instrument  to  the  gum  tissue  beyond  and  this 
accident  should  be  well  guarded  against  by  first  securing  a  pos- 
itive and  sufficient  hand  rest. 

By  the  Pull-Cut  Method  the  blade  of  the  scaler,  which  has  a  hoe 
point  of  about  twenty-eight  degrees,  is  first  passed  under  the  free 
margin  of  the  gum,  its  point  engaged  on  the  ledge  of  the  calculus 
and  its  removal  accomplished  by  a  pulling  force  applied  toward 
the  crown  of  the  tooth,  or  in  a  plane  parallel  vvdth  the  long  axis  of 
the  tooth.  Care  should  be  taken  in  passing  the  instrument  under 
the  free  margin  not  to  lacerate  the  gums.  Pen  grasp  should  be 
used  and  a  secure  hand  rest  obtained  before  making  an  effort  to 
remove  the  deposit. 

The  First  Teeth  to  Be  Scaled  is  not  important,  yet  if  attention 
is  first  directed  to  the  lingual  surfaces  of  the  lower  incisors,  we 
are  able  to  create  an  impression  upon  our  patients  of  the  impor- 
tance of  the  work  in  hand.  It  is  here  we  generally  find  the  heavi- 
est deposits  and  by  removing  these  first,  and  allowing  them  to 
fall  in  the  mouth  the  patient  is  fully  awakened  to  the  need  of  the 
service  being  rendered.  The  same  impressions  never  seem  possible 
if  the  removal  of  the  larger  masses  is  left  until  the  last. 

The  Proximal  Surfaces  Are  Best  Scaled  with  the  pruning  hook, 
draw-cut  scaler  or  the  straight  push-cut  having  a  very  thin  blade 
and  about  a  twenty-three  degree  bevel. 

These  proximal  surfaces  will  need  such  attention  more  from  the 
deposit  of  serumal  calculus  than  from  the  salivary  variety,  which 
is  only  present  in  the  proximal  surfaces  after  gum  recession. 

The  Removal  of  Serumal  Calculus  is  much  more  difficult  than 
salivary,  as  all  of  the  work  is  done  under  the  cover  of  the  gum. 
which  requires  delicacy  of  touch  and  the  highest  degree  of  digital 
skill. 

Calculus  Must  Be  Distinguished  From  Cementum,  bone  and  soft 
tissues,  simply  by  the  sensation  of  touch  conveyed  through  contact 
of  the  instrument  with  the  structures  in  question. 

The  Surface  of  Eoots,  where  the  attachment  of  the  perice- 
mentum has  been  lost,  must  be  carefully  examined  and  the  re- 
moval of  all  calculus  accomplished,  and  the  root  or  roots  thor- 
oughly polished,  as  the  gum  will  not  regain  health  where  particles 
of  the  deposit  remain.  Several  sittings  are  often  necessary  to  ac- 
complish satisfactory  results. 

Pyorrhea  Alveolaris.     The  desire  to  keep  this  book  within  eer- 


PROPHYLACTIC    TREATMENT    OF    THE    MOUTH  185 

tain  limitations  prevents  the  consideration  of  pyorrhea  in  its  treat- 
ment. However  the  foregoing  procedure  will  go  far  towards  the 
prevention  and  cure  of  pyorrhea  alveolaris.  In  fact  thorough 
prophylaxis  is  the  prime  essential  in  the  treatment  of  that  disease. 

The  Removal  of  Green  Stain  is  principally  accomplished  by  the 
application  of  some  abradent,  as  pumice  stone,  with  a  revolving 
brush  in  the  dental  engine.  This  also  polishes  the  croAvns  of  the 
teeth,  removing  the  small  particles  of  calculus  still  adhering  to 
them  after  scaling. 

Hydrogen  dioxide  (HoO,)  added  to  the  powdered  pumice  in 
place  of  water  Avill  assist  in  removing  the  stains  and  particularly 
green  stain,  of  which  it  is  a  partial  solvent.  Following  the  use  of 
pumice  the  gums  should  be  thoroughly  syringed  with  water  to  re- 
move any  trace  of  tlie  pumice,  which  is  insolul)le  in  the  mouth  and 
should  not  be  left  around  the  free  margins  of  the  gums. 

A  Clean  New  Brush  Wheel  should  be  used  and  a  fresh  mix  of 
the  powder  made  for  each  patient  as  a  means  of  preventing  the 
transmission  of  disease  as  well  as  from  a  standpoint  of  cleanliness. 
As  well  might  our  patients  be  asked  to  all  use  the  same  toothbrush^ 
a  thing  not  thought  of,  even  by  members  of  the  same  family. 

The  Removal  of  Sordes  is  a  matter  which  must  be  left  to  the  ef- 
forts of  the  patients.  Its  accumulation  about  favorable  portions 
of  the  teeth  and  mouth  is  but  the  matter  of  a  night  or  a  day  arid 
upon  its  speedy  and  frequent  removal  depends  the  salvage  of  the 
teeth  from  the  ravages  of  caries. 

The  Toothbrush  is  the  one  great  cleansing  agent  and  nine-tenths 
of  the  removal  of  sordes  is  accomplished  purely  by  mechanical  ab- 
rasion through  the  movements  of  the  bristles  of  the  brush  over  the 
surface  of  the  teeth.  The  movements  of  the  bristles  should  be  not 
only  crosswise  to  the  long  axis  of  the  teeth,  but  also  from  root  to 
crown  and  vice  versa,  that  the  travel  of  the  bristles  nmy  parallel 
the  gingival,  enter  the  embrasures  and  traverse  the  grooves  and 
fissures. 

Hydrogen  Dioxide  Is  the  Only  Agent  Avhich  can  be  used  in  the 
moutli  ill  sufficient  strength  to  dissolve  sordes  and  not  injure 
either  the  hard  or  soft  oral  tissues.  This  may  be  used  either  upon 
the  brush  or  as  a  mouth  Avash.  The  dissolution  of  sordes  is  accom- 
plished by  oxidation. 

The  Massage  of  the  Gums  is  advised  to  i-eiiiove  all  nnsolidified 
calculu.s,  food  particles  and  other  foreign  substances  from  beneath 
the  free  margins  of  the  gums  as  this  appears  to  be  the  only  satis- 


186  OPERATIVE   DENTISTRY 

factory  method  of  cleansing  these  spaces.  The  massage  is  also 
most  beneficial  to  the  gums.  It  stimulates  the  circulation,  retards 
tissue  waste  and  lessens  the  deposit  of  serumal  calculus,  and  in  ad- 
dition forces  away  that  which  has  been  precipitated  before  it  has 
an  opportunity  to  solidify. 

Instructions  to  Patients  as  to  the  care  of  their  teeth  is  an  all- 
important  duty  of  the  dentist,  not  only  from  the  standpoint  of 
what  is  best  for  the  patient,  but  much  of  the  dentist's  reputation 
as  an  operator  depends  upon  the  subsequent  care  given  the  teeth 
by  the  owner  following  the  making  of  fillings,  for  upon  their  en- 
vironment depends  their  permanency.  Comparatively  few  indi- 
viduals know  how  to  properly  care  for  the  mouth  and  many  will 
insist  to  their  dentist  that  they  are  most  careful  of  their  oral  hab- 
its when  upon  examination,  the  dentist  finds  surfaces  which  appear 
never  to  have  been  cared  for  in  the  least.  They  have  failed  to 
reach  these  surfaces  with  their  brush. 

The  Technic  of  Proper  Brushing  should  be  thoroughly  ex- 
plained, with  special  reference  to  reaching  the  surface  which  they 
seem  to  be  neglecting.  Instruct  them  as  to  the  massage  of  the 
gums  with  the  finger  tips,  rubbing  not  only  crosswise  but  also 
from  root  to  crown,  assuring  them. that  if  the  gums  bleed  easily  it 
is  all  the  more  essential  that  they  repeat  the  operation  and  that 
finally  they  will  regain  their  normal  health  and  then  they  will  not 
bleed  under  the  treatment  advised. 

The  Use  of  Floss  Silk  for  passing  through  the  proximal  spaces 
to  clean  contacting  surfaces  by  wiping  off  the  embrasures  and 
reaching  points  inaccessible  to  the  brush,  should  be  demonstrated 
to  the  patient. 

Care  should  be  taken  not  to  snap  the  thread  past  contact  points 
as  it  may  lacerate  the  gums. 

Toothpicks  have  no  place  in  the  care  of  the  teeth  and  should  be 
prohibited  by  law,  especially  those  of  soft  wood  so  commonly 
found  on  the  market  and  at  public  eating  houses.  Their  square 
corners  and  slivered  ends  irritate  the  gums,  causing"  their  disease 
and  recession  thereby  destroying  the  natural  protection  to  the 
most  vulnerable  portions  of  the  teeth. 


CHAPTER  XXXII. 
EXCLUSION  OF  MOISTURE 

The  Exclusion  of  Moisture  from  most  operations  upon  the  teeth 
is  essential  to  the  successful  manipulation  of  most  filling  materials, 
the  sterilization  of  tooth  structures  and  the  prevention  of  infec- 
tion, the  cleanliness  of  cavity  walls  and  margins,  that  a  perfect 
view  of  the  cavity  may  be  obtained,  that  the  extent  of  decalcifica- 
tion may  be  observed,  to  diminish  the  pain  of  operations  on  living 
dentine  and  to  protect  the  soft  tissues  from  injury  in  the  use  of 
caustic  drugs,  as  well  as  to  save  time  of  both  patient  and  operator. 

The  Methods  of  Securing  Dryness  during  operations  are  here 
given. 

The  Rubber  Dam,  invented  and  given  to  the  dental  profession  in 
1864  by  Dr.  Sanford  C.  Barnum,  of  New  York  City,  is  widely  used. 

Absorbents,  as  napkins,  cotton  rolls  and  pads  packed  about  the 
teeth  and  near  the  mouths  of  ducts,  assisted  by  specially  con- 
structed clamps  upon  the  teeth  are  also  used.  Dryness  is  also  se- 
cured by  the  )'.se  of  the  saliva  ejector  whereby  the  mouth  is  con- 
tinually drained  of  the  secretions. 

The  Objections  to  the  Use  of  the  Rubber  Dam  are  entirely  on 
the  part  of  the  patient  and  can  generally  be  traced  to  awkward 
and  unskilled  handling  on  the  part  of  the  operator.  Every  oper- 
ator should  become  dextrous  with  each  method,  that  he  may  em- 
ploy the  one  most  expedient  in  every  case,  using  the  one  least 
objectionable  to  the  patient. 

The  Neglect  of  Dryness  in  dental  operations  is  to  invite  disaster 
in  root  canal  treatment,  as  Avell  as  short  life  to  all  fillings  so  placed, 
and  the  operator  who  makes  it  a  practice  to  neglect  this  essential, 
obtains  only  a  ^lartial  success  in  that  which  he  attempts. 

So  Important  Is  Dryness  that  a  patient  should  be  warned  that 
a  certain  operation,  where  moisture  has  been  allowed  to  flood  the 
field,  is  short-lived  at  best  and  is  liable  to  failure  from  this  cause. 
Such  conditions  seldom  arise  but  are  occasionally  met  with,  due 
to  location  and  extent  of  decay  and  also  from  the  fact  that  there 
are  some  patients  who  are  nauseated  by  the  presence  of  the  dam 
or  absoj'bents  about  all  but  the  most  anterior  teeth. 

All  Filling  Materials  are  better  manipulated  under  dry  condi- 
tions at  some  stage  of  the  operation,  porcelain  being  the  only  one 
demanding    moist    conditions  at  any  stage  of  the  process.     This 

187 


188  OPERATIVE   DENTISTRY 

moisture  in  porcelain  filling  is  only  required  to  preserve  the  shade 
of  the  tooth  substance  to  be  imitated  in  the  fused  filling. 

Those  to  Which  Dryness  Is  Most  Essential  are  silicate,  cohesive 
gold,  cement  amalgam  and  gutta-percha,  named  in  the  order  of  the 
importance  of  the  demands.  It  is  true  that  all  of  these  excepting 
silicate  may  be  successfully  manipulated  under  moist  conditions, 
but  the  effort  is  greater  and  the  certainty  of  success  is  materially 
decreased. 

The  Exclusion  of  Moisture  for  Sterilization  and  the  prevention 
of  infection  is  imperative  in  the  last  stages  of  cavity  preparation, 
as  it  is  physically  impossible  to  properly  perform  the  toilet  of  the 
cavity  and  properly  sterilize  the  same  when  flooded  or  even  under 
moist  conditions. 

The  Proper  Treatment  of  Pulp  Canals  cannot  be  accomplished 
when  flooded  by  the  oral  fluids  to  say  nothing  of  the  introduction 
of  a  permanent  root  filling.  The  saliva  is  at  all  times  impregnated 
with  various  forms  of  bacteria.  Its  presence  invites  failure  by  pre- 
venting sterilization  of  canals  already  septic  and  permitting  the 
re-infection  of  those  already  sterile. 

Cavity  Walls,  and  particularly  the  beveled  margins,  must  be 
freshly  cut  and  planed  after  being  moistened  before  the  introduc- 
tion of  a  filling,  as  this  is  the  only  means  of  having  an  absolutely 
clean  surface.  We  may  resort  to  absorbing  and  evaporating  the 
moisture  from  the  walls  and  margins  of  a  cavity,  but  there  will 
invariably  be  left  a  residue  or  film  upon  the  surface  which  is  solu- 
ble in  the  oral  fluids.  No  amount  of  pressure  in  introducing  the 
filling,  be  it  rubber,  amalgam  or  cohesive  gold,  will  displace  the 
moisture  absorbed  by  the  cavity  surfaces,  hence  we  have  this  layer 
of  moisture  or  sediment  intervening  the  filling  and  cavity.  This 
will  be  exchanged  in  course  of  time  for  that  upon  the  outside 
carrying  with  it  bacteria  and  the  products  of  fermentation  or  lac- 
tic acid  and  secondary  caries  is  the  result.  Bacteria,  which  are  the 
active  agents  of  caries,  will  go  where  moisture  Avill  not,  and  the 
lactic  acid  which  they  secrete  will  go  where  the  space  is  too  small 
for  the  bacteria.  It  will  therefore  be  readily  seen  that  a  moist  sur- 
face or  one  coated  with  a  residue  of  an  evaporated  mixture, 
whether  medicine  or  saliva,  intervening  between  a  filling  and  a 
cavity  wall,  becomes  a  large  passage  way  for  the  greatest  enemy 
to  tooth  substance — lactic  acid. 

A  Better  View  of  the  Cavity  Is  Obtained  When  Dry,  as  its  out- 
lines become  more  distinct  and  its  size   and   shape  better  defined. 


EXCLUSION    OP    MOISTURE  189 

No  mechanic  ever  thinks  of  trying  to  accomplish  his  best  work 
with  the  object  submerged  in  moistui-e.  The  rays  of  light  are 
broken,  objects  are  distorted  and  distances  misjudged.  The  dentist 
■who  does  not  effectually  exclude  the  moisture  from  the  immediate 
neighborhood  of  a  cavity  will  catch  only  a  glimpse  now  and  then 
of  portions  of  a  cavity,  this  being  particularly  true  of  the  gingival 
wall,  except  in  cases  of  gum  recession. 

The  Extent  of  Decalcification  of  both  dentine  and  enamel  is  di- 
agnosed only  when  dryness  is  obtained  to  bring  out  the  colors  and 
shades  of  each  incident  to  these  conditions.  It  is  impossible  to 
make  proper  cavity  extension  until  the  cavity  has  been  made  dry 
and  so  maintained  for  some  time,  as  this  is  often  the  only  means  of 
detecting  superficial  caries.  Semi-decalcified  tooth  substance,  when 
moist,  materially  resembles  the  healthy  structures  and  must  be 
dried  to  detect  its  injured  condition. 

The  Pain  of  Cavity  Excavation  is  materially  decreased  by  the 
extraction  of  the  moisture  from  the  dentine.  The  protoplasm 
within  the  dental  tul)ules  is  the  means  of  transmitting  the  sensa- 
tion of  pain  to  the  vital  pulp.  Water  is  a  large  constituent  of  pro- 
toplasm and  the  extraction  of  this  moisture  through  extreme  and 
continued  dryness  removes  the  media  of  sensitiveness.  It  is  there- 
fore but  humane  that  the  cutting  of  dentine  be  done  with  the  mois- 
ture excluded. 

When  Using-  Caustic  and  Concentrated  Drugs  the  moisture 
should  be  excluded,  that  the  drug  may  not  be  carried  away  to  the 
injury  of  adjacent  tissues  and  that  the  drugs  may  not  be  diluted 
to  deti'act  from  their  efficiency  in  accomplishing  that  for  which  they 
were  used.  Drugs  placed  in  the  cavities  of  teeth  with  moist  mar- 
gins even  when  placed  under  fillings  of  rubber,  cement  or  amalgam, 
will  follow  the  moisture  of  these  margins  to  join  that  without  and 
great  damage  to  the  surrounding  tissues  often  results  from  no  other 
cause  than  a  hiok  of  the  exclusion  of  moisture  during  the  operation. 

As  a  Time  Saver  the  exclusion  of  moisture  should  not  be  ovei"- 
looked.  With  a  dry  cavity  the  continued  uninterrupted  view  per- 
mits of  more  continuous  woi-k  by  the  dentist.  He  does  not  have  to 
wait  for  the  patient  to  expectorate,  make  a  few  remarks  and  leisurely 
resume  his  position  in  the  chaii-,  not  always  in  the  position  desired 
for  operating.  The  opei-atoi-  will  also  be  saved  nnich  time  in  dry- 
ing the  cavity  after  each  flooding.  All  this  takes  valuable  time,  much 
more  than  is  re(|uired  tf)  adjust  a  dam. 

The  Rubber  Dam  is  the  most  (IcpciMhihIc  nicans  of  securing  a  d?-y 


190  OPERATIVE   DENTISTRY 

field  for  operating  and  its  proper  and  speedy  adjustment  should  be 
mastered.  It  is  made  in  three  thicknesses ;  heavy,  light  and  medium, 
the  medium  being  the  weight  best  adapted  for  all  purposes  where 
only  one  weight  is  to  be  kept  at  hand. 

The  Size  and  Shape  is  of  little  importance  so  long  as  it  com- 
pletely covers  the  mouth  after  it  has  been  made  to  isolate  the  teeth 
desired,  as  well  as  cover  the  chin  and  extend  to  either  side  of  the 
mouth  sufficient  for  the  proper  engagement  of  the  holder.  This  will 
require  a  piece  from  five  to  six  inches  square,  for  all  cases  back  of 
the  six  anterior  teeth  and  is  most  frequently  the  size  used  on  the 
anterior  teeth.  However,  some  economy  of  rubber  dam  may  be  prac- 
ticed by  cutting  these  squares  in  two  triangular  pieces,  each  of  which 
will  do  for  a  separate  case.  These  are  applied  with  the  diagonal  of 
the  quadrilateral    (hypotenuse)    uppermost. 

The  Holes  to  Receive  the  Teeth  should  be  of  the  proper  size  and 
smoothly  cut,  otherwise  there  is  an  increased  liability  of  being  torn 
in  adjustment.  This  is  best  done  by  the  use  of  the  rubber  dam 
punch  to  be  had  at  dental  depots.  However,  in  the  absence  of  this, 
a  very  good  result  is  obtained  by  drawing  the  rubber  tightly  over  a 
tapering  round  handle  of  an  instrument  and  touching  the  sharp  edge 
of  a  knife  to  the  rubber  down  the  side  of  the  handle  when  a  per- 
fectly round  piece  will  be  cut  out. 

The  Distance  Between  the  Holes  will  vary  according  to  the  space 
between  the  teeth,  the  height  of  the  festoon  of  the  gum,  the  weight 
of  the  dam  and  the  size  of  the  teeth  to  be  engaged.  Generally  speak- 
ing, the  holes  are  cut  from  two  to  four  millimeters  apart  in  medium 
dam.  The  lighter  the  dam  the  farther  apart  should  be  the  holes. 
The  holes  are  farther  spaced  with  extremely  large  gum  festoons,  also 
when  there  is  a  considerable  gum  recession.  If  the  holes  are  too  close 
together  in  above  condition  the  dam  may  not  cover  the  entire  proxi- 
mal tissues  and  a  leakage  may  occur,  or  the  gum  septa  may  be  un- 
duly compressed  and  permanent  injury  result  from  strangulation. 
If  the  holes  are  too  far  apart  the  rubber  will  wrinkle  and  bag  at  the 
proximal  spaces  and  seriously  hinder  operations  in  these  localities. 

The  Location  of  the  Holes  in  the  piece  of  rubber  dam  depends 
upon  the  location  of  the  tooth  to  be  operated  upon  and  the  teeth 
to  be  isolated.  A  beginner  will  do  well  to  first  place  the  dam  over 
the  mouth  in  the  position  desired  for  the  outside  edges,  request  the 
patient  to  open  the  mouth  and  with  the  finger  cause  the  dam  to  come 
in  contact  with  the  occlusal  surfaces  of  the  teeth  it  is  intended  to 
include  and  then  punch  the  holes  as  this  trial  indicates.     By  this 


EXCLUSION    OF    MOISTURE  191 

method  the  operator  will  soon  become  familiar  with  the  location  in 
each  case. 

The  Number  of  Teeth  Isolated  depends  upon  the  location  and  the 
operation  to  be  performed.  For  the  short  treatment  cases,  sometimes 
the  placing  of  one  or  two  teeth  under  the  dam  will  suffice,  but  in 
most  cases  where  fillings  are  to  be  made  and  polished,  from  five  to 
eight  teeth  should  be  included  that  a  good  view  of  the  field  of  opera- 
tion may  be  had  and  the  loose  folds  of  dam  carried  farther  away  to 
avoid  them  catching  in  the  revolving  points  of  the  engine. 

With  Anterior  Teeth  the  first  bicuspid  tooth  of  either  side  should 
be  included,  as  the  cuspid  from  its  conical  shape  is  many  times 
unsafe  for  a  final  ligature. 

With  Bicuspids  and  Molars  as  the  objective  teeth  in  an  opera- 
tion, there  should  also  be  included  the  teeth  anterior  to  the  median 
line. 

The  Clamp  should  be  placed  on  the  tooth  back  of  the  one  to  be 
operated  upon,  excepting  in  mesial  cavities  in  second  molars  when 
the  clamp  may  be  placed  on  the  second  molar,  thereby  avoiding  the 
clamping  of  the  third  molar  except  when  absolutely  necessary,  as 
with  distal  cavities  in  second  molars. 

The  Placing'  of  the  Dam  requires  the  freedom  of  both  hands  of 
the  operator,  and  the  aid  of  an  assistant  is  of  value.  The  necks  of 
the  teeth  upon  which  the  rubber  dam  is  to  be  placed  should  be  cleansed 
of  all  calculus  and  sordes  and  fllooded  with  a  jet  of  water  from  the 
syringe.  If  the  gums  show  hypersensitiveness  they  should  be  bathed 
in  a  solution  of  novocain,  restricting  its  use  to  the  gingival  borders. 
Waxed  silk  should  be  passed  through  the  proximal  spaces  to  clean 
them  and  prove  access  for  the  rubber.  If  sharp  margins  of  cavities 
cut  the  silk  these  should  be  dulled  by  passing  a  thin  ribbon  saw 
through  the  proximal  space  or,  with  the  chisel,  carry  the  margin 
sufficiently  into  the  embrasure  to  give  access. 

AVhen  teeth  are  in  close  contact  so  that  the  silk  thread  is  passed 
with  difficulty,  the  rubber  can  be  made  to  pass  more  readily  by  the 
use  of  soap,  which  is  done  by  placing  the  row  of  holes  on  the  ball 
of  the  index  finger,  occlusal  .side  up,  and  rubbing  the  soaped  fingers 
of  the  other  hand  across  the  holes. 

The  Occlusal  Side  of  the  Rubber  Dam  is  that  side  which  is  to- 
war<l  1ln'  occliis;!]  surface  when  the  dam  is  in  position. 

The  Gingival  Side  is  liie  o])p()site  side  and  is  next  lo  Ihe  gingival 
margins  when  the  dam  has  been  applied  to  the  teeth. 

The  Method  of  Applying  the  Dam   is   afreclcd   l)y   Ihe  fact  of 


192  OPERATIVE   DENTISTRY 

whether  a  clamp  is  used  or  not  and  kind  of  clamp  when  one  is  used. 

With  the  Anterior  Teeth  we  do  not  generally  use  a  clamp  and  the 
rubber  is  placed  by  commencing  at  one  side  and  then  crowding  the 
rubber  through  each  proximal  space  in  the  order  they  should  go, 
until  the  opposite  side  is  reached.  The  rubber  dam  holder  should 
be  applied  to  one  side  before  commencing  the  adjustment,  and,  as 
soon  as  the  teeth  have  been  forced  through  the  holes,  the  other  side 
of  the  holder  should  be  attached. 

With  Posterior  Teeth  the  holder  should  be  attached  to  the  short 
side  of  the  rubber  to  prevent  curling  into  the  mouth,  which  would 
be  the  same  side  of  the  dam  as  the  teeth  are  situated  in  the  mouth, 
right  or  left.  Adjust  clamp  to  be  used  as  this  tooth  receives  first 
attention,  while  the  remaining  teeth  are  one  by  one  pushed  through, 
until  the  most  -anterior  one  is  reached,  when  the  remaining  side  of 
the  rubber  is  secured  with  the  holder. 

To  Prevent  Leakage  Around  the  Teeth  the  edges  of  the  holes 
must  turn  toward  the  roots.  This  is  accomplished  by  first  pressing 
the  dam  well  against  the  gums  while  grasping  the  rubber  on  either 
side  of  the  tooth  and  drawing  it  tight,  then  releasing  the  rubber  so 
that  it  slackens  and  then  gently  moving  it  occlusally.  This  will  gen- 
erally have  the  effect  of  inverting  the  edges.  If  inversion  is  not 
complete  pass  a  small  blunt  instrument,  as  a  spatula  or  dull  ex- 
plorer, around  the  gingival  to  turn  the  edge  under. 

The  Use  of  the  Ligature  is  to  assist  in  inverting  the  edges  of  the 
holes  in  the  rubber  dam  and  to  secure  the  edges  about  the  teeth  in 
this  position  against  displacement  by  the  movements  on  the  part  of 
the  patient  or  the  operator. 

Caution  in  the  Use  of  Ligatures  is  most  important  as  much  per- 
manent injury  is  done  the  gingival  attachments  by  the  careless  crowd- 
ing of  these  on  the  dental  ligaments.  This  is  particularly  the  case 
where  the  proximal  gum  festoons  are  high  as  in  these  cases,  espe- 
cially with  young  people,  the  attachment  to  the  tooth  is  also  high. 
A  tight  ligature  tends  to  encircle  the  tooth  in  a  straight  line  and 
would  thereby  ride  down  the  high  proximal  attachments,  if  the  lig- 
ature is  crowded  to  the  full  height  both  labially  and  lingually.  Hence 
either  the  labial  or  the  lingual  should  not  be  crowded  to  the  full  height 
of  the  crown. 

Ligatures  Are  Made  of  well-waxed  floss  specially  prepared  for 
the  purpose,  cut  into  lengths  of  about  five  or  six  inches.  Some  econ- 
omy may  be  practiced  where  three  teeth  are  to  receive  ligatures  by 
starting  with  a  piece  about  twelve  inches  long.  Tie  the  first  tooth 
in  the  center  of  the  strand  and  when  the  ends  are  cut  off  enough  re- 


EXCLUSION'   OF    MOISTURE  193 

mains  for  the  other  two,  thus  getting  three  out  of  the  amount  usually 
used  for  tAvo. 

The  Cutting  of  the  Loose  Ends  may  be  practiced  for  all  the  teeth 
except  the  lower  anterior,  cutting  two  or  three  millimeters  from  the 
knot.  With  the  lower  anterior  teeth,  ends  of  two  or  three  inches 
should  be  left  from  each  knot  and  the  farther  ends  of  all  tied  to- 
gether, and  weighted  to  overcome  the  efforts  of  the  patient  to  ele- 
vate the  lower  lip.  which  endangers  the  security  of  the  dam. 

The  Most  Popular  Knot  for  tying  ligatures  is  the  "surgeon's 
knot,"  either  full  or  half.  This  knot  is  made  by  passing  the  ends 
around  each  other  twice  before  each  tie  is  made,  for  the  ''full  sur- 
geon's knot,"  while  for  the  "half  surgeon's  knot"  this  is  done  with 
only  the  first  half  of  the  knot. 

The  "Wedelstaedt  Tie"  is  even  more  secure  than  the  above  and 
is  made  by  using  the  first  half  of  a  "surgeon's  knot"  on  the  lingual 
side  of  the  tooth  first  and  then  passing  contacts  with  the  ends  on 
either  side  of  the  tooth,  complete  the  operation  with  a  "half  sur- 
geon's knot"  on  the  labial,  thus  circling  the  tooth  with  two  strands. 

The  Removal  of  Ligatures  from  the  tooth  when  the  operation  has 
been  completed  should  be  accomplished  before  the  rubber  dam  has 
been  disturbed,  and  is  best  done  by  the  use  of  a  small  sharp-pointed 
knife  as  a  No.  1  gum  lancet.  The  thread  should  be  severed  to  one 
side  of  the  knot  on  the  labial  or  buccal  side,  and  by  grasping  the  knot 
with  a  pair  of  pliers,  the  thread  is  pulled  through  from  that  side. 

Where  Amalgam  Fillings  Have  Just  Been  Completed  in  a  prox- 
imal space  the  ligature  about  a  tooth  so  filled  as  well  as  that  around 
the  proximating  tooth  should  be  cut  so  that  the  part  lying  gingivally 
from  the  fresh  amalgam  will  be  loosened  and  will  pass  out  to  the  lin- 
gual embrasure.  The  ligature  about  a  tooth  in  which  there  has  just 
been  completed  a  filling  in  both  the  mesial  and  distal  should  be  cut 
on  the  lingual  portion.  This  action  will  result  in  both  ends  being 
loose  ends.  Attention  to  this  point  will  prevent  the  ligature  plowing 
a  ditch  in  the  amalgam  and  destroying  the  filling,  in  many  cases,  at 
the  gingival-cavo-surfaee. 

A  Good  Rule  to  Remember  with  mesial  fillings  is  to  cut  to  the 
mesial  of  the  knot ;  with  distal  fillings  cut  to  the  distal  of  the  knot 
and  where  a  tooth  has  both  mesial  and  distal  fillings  cut  ligature  on 
the  liniru!)]. 

The  Selection  of  the  Clamp  should  be  luado  and  then  tried  on 
the  tooth  it  is  intended  to  be  used  upon.  One  should  be  secured 
that  has  jaws  which  fit  the  contour  of  the  tooth  at  its  gingival  bor- 
der, that  will   rfmain  in  position  and  yet  docs  not  hug  the  tooth  so 


194  OPERATIVE   DENTISTRY 

tightly  as  to  cause  the  patient  pain  or  in  any  way  injure  the  soft 
tissues. 

The  Method  of  Applying  the  Clamp  with  the  dam  is  to  stretch 
the  rubber  over  the  clamp,  then  apply  the  clamp  forceps  and  carry 
all  to  position  on  the  desired  tooth,  using  the  hole  in  the  dam  thus 
intended  as  a  means  of  getting  a  view  of  the  tooth  to  be  clamped, 
which  aids  in  the  placing. 

Some  of  the  older  makes  of  clamps  require  that  they  first  be  placed 
in  position  on  the  tooth  and  then  with  the  first  fingers  of  each  hand 
the  hole  is  distended  in  the  rubber  dam  sufficiently  to  permit  it  to 
slip  over  the  bow  of  the  clamp. 

In  Using  Cervical  Clamps  for  cavities  on  the  buccal  and  labial 
surfaces  in  the  gingival  third  the  dam  is  first  passed  to  position  and 
then  the  clamp  applied. 

The  Removal  of  the  Rubber  Dam  is  accomplished  by  the  follow- 
ing order  of  procedure: 

First — The  removal  of  the  ligations  as  before  described. 

Second — Pull  the  rubber  to  the  buccal  or  labial  and  with  a  sharp 
pair  of  scissors  cut  strips  passing  between  the  teeth. 

TJiird — Disengage  one  side  of  the  dam  holder. 

Fourth — With  the  right  hand  remove  the  clamp  which  should 
be  holding  the  rubber  dam,  remove  all  clear  of  the  mouth  immedi- 
ately, as  the  patient  does  not  take  kindly  to  any  delays  at  this 
stage  of  the  procedure. 

FiftJi — Inspect  the  rubber  to  see  if  it  has  all  been  removed. 

SixtJi — Inspect  the  teeth  for  any  portions  of  rubber  dam,  liga- 
tures or  stray  particles  of  filling  material.  Now  proceed  to  knead 
the  gums  with  the  fingers,  at  the  same  time  fiooding  them  with 
a  forceful  stream  of  water  from  the  syringe,  to  cleanse  them  and 
to  re-establish  circulation. 

The  Use  of  Absorbents  may  be  resorted  to  in  place  of  the  rubber 
dam  for  short  operations  and  more  particularly  with  the  upper 
teeth  as  these  are  the  most  easily  managed.  Absorbents  are  to 
be  had  in  the  market  in  the  form  of  rolls  and  napkins  at  small  cost 
and  are  to  be  discarded  after  once  used,  which  is  the  only  hygienic 
method.  In  their  use  particular  attention  must  be  paid  to  the 
mouths  of  the  ducts  responsible  for  the  most  abundant  secretions 
and  the  absorbents  so  placed  as  to  not  only  readily  absorb  the  fluid 
which  is  ejected,  but  also  that  they  compress  the  ducts  thereby  re- 
stricting the  flow. 


CHAPTER  XXXIII. 
TKEATMEXT  OF  HYPERSENSITIVE  DENTINE. 

Hypersensitive  Dentine  is  dentine  which  is  more  than  normally 
responsive  to  mechanical  or  chemical  irritation. 

Normal  Healthy  Dentine  is  only  slightly  sensitive,  bnt  Avhen  ex- 
posed to  abnormal  conditions  and  irritating  agents  it  may  become 
excrnciatingly  hypersensitive. 

The  Sensations  Are  Conveyed  to  the  Pulp  by  means  of  the  con- 
tents of  the  dental  tubules  Avhich  are  prolongations  of  the  odonto- 
blasts. The  odontoblasts  are  thickly  surrounded  by  the  terminal 
fibers  of  the  nerves  Avithin  the  pulp. 

The  Contents  of  the  Tubuli  is  largely  protoplasm  and  although 
this  has  the  power  of  transmitting  sensation  in  response  to  irrita- 
tion, it  has  not  yet  been  demonstrated  that  the  nerve  fibers  enter 
the  tubuli  or  penetrate  their  contents.  Hence  it  cannot  be  said 
that   there   is  nerve  tissue  within  the   dentine. 

The  Direct  Cause  of  Sensitive  Dentine  is  the  loss  of  the  enamel 
which  is  the  natural  covering  of  the  dentine. 

The  Most  Common  Agent  in  the  removal  of  this  normal  covering 
is  caries,  which  exposes  the  dentine  to  mechanical  injury  through 
contact  with  foreign  substances  and  chemical  irritants,  particularly 
the  acids  of  fermentation. 

Rapidity  of  Caries  has  much  to  do  with  the  degree  of  hyper- 
sensitiveness  in  dentine,  as  shown  in  the  white  and  light  stages 
or  rapid  forms  of  caries  wherein  the  sensitiveness  is  most  exalted, 
while  with  the  dark,  yellow  and  brown  varieties  it  is  not  so  marked 
and  with  the  black  or  slow  progressing  form  of  caries  the  sensitive- 
ness is  scarcely  above  normal. 

The  Most  Sensitive  Part  of  a  Carious  Tooth  is  at  the  junction  of 
the  dentine  with  the  enamel  or  cemcntum  at  the  periphery  of  the 
tubuli.  It  is  therefore  evident  that  the  second  stage  of  caries  will 
show  a  highei'  degree  of  hypersensitive  dentine  than  the  deep-seated 
stages  and  that  the  preliminary  steps  in  cavity  preparation  in  this 
division  of  caries  will  be  more  painful  than  the  deeper  cuts  into  the 
deiiliiie.  as  then  the  more  sensitive  part  has  been  passed. 

Mechanical  Abrasion  is  also  an  agent  which  produces  hyper- 
senHitivc  dentine  1)\'  fii-st  wearing  away  the  enamel  and  then  en- 
croaching on  the  dentine.  However,  this  process  may  be  so  slow 
and  the  irritation  so  slight  as  to  act  as  a  stimulus  to  the  odontoblasts 

195 


196  OPERATIVE   DENTISTRY 

and  result  in  the  obliteration  of  the  dental  tnbuli  by  the  deposit  of 
calcific  matter  termed  ''tubular  calcification."  When  this  is  the 
result  all  sensation  may  be  absent. 

Exposure  of  Cementum  through  gum  recession  is  another  excit- 
ing cause  of  hypersensitive  dentine  aggravated  by  allowing  the  ac- 
cumulation of  sordes  about  the  exposed  cementum. 

Abnormal  Oral  Secretions  often  produce  hypersensitive  dentine 
and  may  be  particularly  looked  for  in  the  convalescent  stages  of 
fevers,  as  well  as  in  dyspepsia,  neuralgia,  pregnancy,  pulmonary  tu- 
berculosis and  acute  rheumatism. 

Hypersensitive  Dentine  is  found  in  poorly  calcified  dentine  in- 
cluding the  teeth  of  the  growing  child;  teeth  that  have  not  been 
erupted  for  more  than  a  few  months;  the  teeth  of  those  who  follow 
indoor  lives,  particularly  if  they  are  under  a  heavy  mental  strain, 
as  well  as  anything  which  may  produce  nervous  irritation  or  debility. 

The  Varying  Temperaments  of  Patients  must  be  studied  and  un- 
derstood to  best  cope  with  the  problem  of  hypersensitive  dentine. 
The  suffering  is  actual  upon  the  part  of  some,  while  there  are  those 
who  magnify  every  pain  and  seem  to  be  able  to  stand  nothing  and 
make  as  much  fuss  about  a  pin  stick  as  it  would  be  possible  for  them 
to  make  were  they  thrust  through  with  a  bayonet.  The  operator  must 
separate  these  classes  and  vary  the  methods.  He  must  understand 
the  actual  conditions  and,  by  kind  words  of  encouragement  and  a 
positive  procedure,  stimulate  the  nervous  to  withstand  the  necessary 
pain.  This  can  only  be  done  when  the  operator  has  full  control  of 
his  own  feelings,  seeing  to  it  that  his  temper  is  not  ruffled,  for,  hav- 
ing lost  control  of  himself,  he  has  no  control  over  the  patient. 

Highly-Wrought,  Nervous  Temperament  is,  by  nature,  sensitive 
to  impressions,  especially  augmented  by  environment  or  occupation 
and  calls  for  the  most  skillful  management  of  both  patient  and  teeth. 
People  of  this  type  are  generally  of  a  high  order  of  intelligence  and 
when  handled  by  a  master  hand  prove  a  most  desirable  clientage. 

Patients  of  This  Temperament  will  permit  being  hurt  for  a  short 
time  provided  something  definite  has  been  accomplished.  They  should 
be  advised  at  times  as  to  the  coming  pain,  and  for  what  purpose  it 
must  be  inflicted,  as  the  forming  of  an  angle  or  the  flattening  of  a 
wall,  explaining,  when  done,  that  that  which  had  been  intended  has 
been  accomplished.  They  will  stand  for  no  awkwardness  or  fumbling 
but  admire  exactness  and  precision  and  are  the  class  which  will  re- 
ward the  dentist  most  liberally  for  painstaking  efforts  and  actual 
achievements.     This  class  make  the  day  long  but  they  serve  to  stim- 


TREATMENT    OF    HYPERSENSITIVE    DENTINE  197 

ulate  the  dentist  to  his  best  efforts  and  work  to  the  advancement  of 
the  really  progressive  operator. 

The  Irresponsible  Individuals  avIio  have  no  mental  or  physical 
stamina  require  a  strong  hand  to  control  them  in  any  emergency  in 
life.  They  go  to  the  dentist  only  when  forced  there  by  pain  or  are 
children  brought  by  their  parents.  While  a  dentist  should  never  be 
harsh  with  any  patient,  yet  this  class  will  necessitate,  many  times, 
stern  commands,  and  a  "why,  of  course"  method.  In  cases  of  this 
character  where  the  operator  has  chosen  to  assume  the  role  of  a  dis- 
ciplinarian, the  stern  proceeding  should  universally  be  tempered  with 
the  kindest  of  tones  before  the  patient  leaves  the  chair,  that  he  may 
depart  with  the  impression  that  the  dentist  is  kind  of  heart  and  has 
been  severe  only  for  the  patient's  good. 

The  Naturally  Cowardly  Patient  who  is  strong,  healthy  and  ro- 
bust, yet  lives  in  mortal  dread  of  any  physical  discomfort,  is  the  hard- 
est class  to  manage.  This  class  of  patients  have  generally  been  raised 
in  luxury  and  taught  by  example  made  possible  by  their  environ- 
ment, that  they  should  not  even  be  inconvenienced.  They  seldom 
work  and  mistake  that  tired  feeling  for  sickness.  To  be  hungry,  cold 
or  warm,  is  described  by  them  as  "simply  terrible."  With  such, 
often  the  best  an  operator  can  do  is  simply  to  temporize  to  keep  the 
teeth  comfortable.  To  attempt  thorough  work  merely  drives  them 
away  to  seek  gas  for  painless  extraction. 

The  Patient  Who  Simulates  Pain  should  be  early  detected  and 
severely  dealt  with.  An  operator  should  remember  that  a  large 
amount  of  the  gesticulation,  grabbing  the  working  hand,  cringing 
and  outcry,  is  simply  voluntary  on  the  part  of  many  patients  to  in- 
form the  dentist  that  he  is  hurting  them.  Most  of  this  can  be  done 
away  with  by  the  following  procedure: 

First  tell  the  patient  that  "this  will  not  hurt  you,"  and  then  pro- 
ceed to  make  the  statement  true  by  working  on  enamel  margins, 
even  to  gently  scratching  on  the  external  surface.  Then  state  to 
the  patient  that  "this  may  hurt  a  little"  and  the  operator  can  pro- 
ceed to  test  the  dentine  for  its  sensitive  portions.  He  may  then  pro- 
ceed to  do  the  less  painful  parts  of  cavity  preparation.  Lastly  when 
it  comes  to  cutting  the  angles  and  cutting  sensitive  portions  the  pa- 
tient should  be  warned  that  this  particular  place  may  be  sensitive 
but  that  a  certain  amount  of  cutting  is  necessary.  Advise  the  pa- 
tient to  hold  still  for  just  a  second  or  two  and  then  he  will  be  allowed 
to  rest.  Caution  him  against  moving  during  this  brief  period  as 
it  will  undo  what  has  been  accomplished,  necessitating  his  withstand- 
ing the  pain  again.     Praise  the  patient  for  his  bravery  when  he  has 


198  OPERATIVE   DENTISTRY 

complied  with  the  request  and  advise  him  as  to  the  work  accom- 
plished. All  this  instills  confidence  into  the  patient  as  to  the  den- 
tist knowing  what  he  is  about  and  as  to  his  knowledge  of  the  place 
and  time  that  pain  may  be  expected.  Nothing  unnerves  a  patient 
so  much  as  to  get  the  slightest  idea  that  the  dentist  is  not  aware  of 
the  pain  he  is  inflicting  or  that  he  has  little  care  for  one's  sufferings 
and  has  no  definite  idea  as  to  when  it  will  end. 

The  True  Simulator  of  Pain  Avill  try  to  make  the  operator  believe 
he  is  causing  pain  when  he  is  not  suffering  at  all,  with  the  idea  that 
the  dentist  will  be  frightened  into  extreme  care  in  his  case.  This 
class  is  easily  detected  by  scraping  an  instrument  on  a  surface  where 
pain  is  impossible,  as  the  external  surface  of  a  tooth.  If  the  demon- 
strations continue  it  is  the  operator's  duty  to  inform  the  patient 
of  the  detection  of  the  attempted  deception  and  that  such  will  not 
be  further  considered,  at  the  same  time  advising  him  to  save  his 
demonstrations  until  he  is  hurt  when  they  will  be  considered,  and 
every  effort  made  to  lessen  the  pain. 

The  Agents  for  Relief  of  Sensitive  Dentine  are : 

Fii^st — Those  which  produce  a  physical  change  in  the  contents  of 
the  tubuli,  as  desiccation,  heat  and  cold. 

Second — Those  agents  which  destroy  or  disorganize  the  contents 
of  the  tubuli,  as  caustics  and  escharotics. 

Third — Those  agents  which,  when  applied,  to  the  dentine,  locally 
or  hypodermically  produce  a  condition  of  analgesia  or  absence  of 
sensibility  to  pain,  termed  local  anesthetics,  and  anodynes  as  phenol, 
menthol,  morphine,  oil  of  cloves,  cocaine  and  novocain. 

Fourth — Those  agents  administered  with  the  view  of  reaching  the 
nerves  of  the  pulp  through  the  general  system  as  bromide  of  potas- 
sium, nitrous-oxide  chloroform,  etc. 

Fifth — The  mechanical  condition  under  which  the  cutting  of  sen- 
sitive dentine  is  done. 

Physical  Agents. 

Desiccation  Is  a  Physical  Agent  of  great  virtue  in  alleviating 
hypersensitive  dentine  and  accomplishes  the  result  by  extracting  the 
moisture  from  the  tubuli,  which  is  a  large  constituent  of  the  proto- 
plasm. 

This  Is  Best  Accomplished  by  first  flooding  the  cavity  with  ab- 
solute alcohol  which  has  an  affinity  for  water,  and  then  directing  into 
the  cavity  a  continuous  stream  of  warm  air  which  is  more  effective 
if  the  temperature  can  be  controlled  so  as  to  gradually  raise  it  to 
the  highest  point  tolerable  to  the  patient.     Painless  cavity  excava- 


TREATMENT    OF    HYPERSENSITIVE    DENTINE  199 

tioii  can  be  accomplished  to  the  depth  of  desiccation  which  will  vary 
with  different  cases. 

A  Continuous  Stream  of  cold  air  will  have  a  similar  action 
through  its  desiccating  effect  and  is  practiced  where  compressed  air 
is  at  hand.  The  force  with  which  the  air  is  contacted  with  the  cav- 
ity walls  is  a  factor  in  its  efficiency. 

Heat  and  Cold  When  Moist  will  produce  physical  changes  in  the 
protoplasm  of  the  tubuli  sufficient  to  destroy  the  sensation  of  pain. 

In  any  locality  of  the  body  a  moderate  rise  in  the  temperature, 
particularly  moist  heat,  quickens  vital  action  and  heightens  func- 
tional activity.  This  is  true  of  sensitive  dentine  and  the  tempera- 
ture must  be  materially  raised  before  a  stage  of  paralysis  is  reached. 

The  Best  Means  of  Applying  This  Method  is  to  direct  into  the 
protected  cavity  a  forceful  fine  stream  of  water  which  can  be  grad- 
ually raised  in  temperature  to  the  point  of  toleration,  cutting  the 
sensitive  part  of  the  cavity  while  the  stream  of  water  is  still  play- 
ing on  the  point  being  operated  upon. 

With  the  Application  of  Cold  to  any  part,  vital  phenomena  of 
every  nature  is  retarded  and  entirely  ceases  with  the  lower  tem- 
peratures. 

The  Best  Method  of  Applying  this  principle  is  to  spray  the  cavity 
with  a  highly  volatile  liquid  as  ethyl  chloride,  sulphuric  ether,  and 
its  combinations  Avith  choloroform.  The  rapid  evaporation  lowers 
the  temperatures,  extracting  the  heat  from  that  with  w^hich  it  comes 
in  contact. 

The  Primary  Pain  in  Applying  these  agents  may  be  lessened  by 
filling  the  cavity,  temporarily  with  stopping,  directing  the  spray  first 
on  this  and  the  surrounding  parts  and  later  removing  the  stopping, 
directing  the  spray  into  the  cavity  without  causing  much  pain,  pro- 
vided there  is  not  a  hyperemic  pulp  within  the  tooth,  in  which  case 
all  llicnnal  changes  must  be  avoided. 

The  Electric  Current  (Cataphoresis)  as  a  physical  agent  to  ob- 
tund  sensitive  dentine  should  be  mentioned.  It  has  been  used  to  as- 
sist in  carrying  various  drugs  into  the  dentine,  to  facilitate  their  ac- 
tivity, l)Ut  its  use  has  proved  so  unsatisfactory,  in  many  ways,  that 
further  description  of  this  method  is  unwarranted. 

Destroying  Agents. 

Caution  in  the  Use  of  Caustics  and  Escharotics  lo  lelieve  sensi- 
tive dcntin(!  in  deep-seated  cavities  will  save  much  pulp  complica- 
tions and  gr(!at  care  must  l)e  exercised  in  their  use  not  only  for  the 
safety  of  the  pulp  I)u1   also  the  soft  tissues  about  the  tooth  must 


200  OPERATIVE   DENTISTRY 

be  effectually  protected.  Many  caustics  are  not  limited  in  their  ac- 
tion and  when  once  applied  on  the  dentine  continue  their  destruc- 
tion to  the  envelopment  of  the  pulp.  Arsenic  trioxide  is  a  notable 
example  of  this. 

Zinc  Chloride  is  one  of  the  oldest  and  most  efficient  remedies  for 
hypersensitive  dentine.  Its  action  is  due  to  its  affinity  for  water  and 
its  coagulating  properties  upon  albumen. 

The  Danger  in  its  Use  in  deep-seated  cavities  is  through  the  lib- 
eration of  hydrochloric  acid,  which  causes  pain  in  case  of  a  nearly 
exposed  pulp.  This  effect  may  be  modified  by  using  it  in  a  solution 
of  one  part  chloroform  and  four  parts  alcohol.  Add  the  zinc  crystals 
to  the  proportion  of  five  grains  to  the  ounce.  Clarify  by  adding  a 
drop  of  hydrochloric  acid. 

The  Methods  of  Using-  Zinc  Chloride  are : 

First — Saturate  a  pellet  of  cotton  with  the  above  solution,  place 
in  the  cavity  and  evaporate  with  a  draft  of  warm  air  from  the  warm 
air  syringe  or  chip  blower. 

Second — Mix  a  thin  paste  of  zinc  oxyehloride  cement.  Paint  the 
sensitive  dentine  with  this  cement  and  cover  with  stopping  or  gutta- 
percha. After  a  few  days  or  weeks,  often,  excavation  may  be  ac- 
complished with  little  pain. 

Caustic  Potassa  and  Carbolic  Acid,  equal  parts  (Robinson's  rem- 
edy), often  relieves  sensitiveness  of  the  dentine  and  is  applied  by 
placing  a  pledget  of  cotton  in  the  cavity,  always  with  the  rubber 
dam  in  position  to  protect  soft  tissues. 

Silver  Nitrate  may  be  employed  to  good  effect  upon  exposed 
surfaces  of  dentine  in  the  posterior  parts  of  the  mouth,  such  as  those 
on  the  occlusal  surface  of  molars'  due  to  abrasions,  or  exposed  ce- 
mentum.  It  reduces  sensitiveness  and  by  forming  the  albuminate 
of  silver  it  retards  decay  even  so  far,  in  some  cases,  as  to  render 
the  surfaces  to  which  it  has  been  applied  immune  to  caries.  On  ac- 
count of  its  discoloring  effect  its  use  is  not  permissible  in  parts  ex- 
posed to  view. 

Formaldehyde.  Formaldehyde  is  a  protoplasmic  poison  and  is  a 
great  desensitizer.  The  author  called  the  attention  of  the  profession 
to  this  method  at  the  "World's  Columbian  Dental  Congress  in  1893 
in  a  paper  before  that  convention.  However,  its  irritating  effects 
are  sometimes  injurious  to  the  pulp  and  great  care  has  to  be  exer- 
cised in  its  use,  particularly  that  there  is  not  a  near  pulp  exposure. 
It  is  of  advantage  if  the  material  can  be  so  combined  as  to  cause 
a  slow  liberation  of  the  formaldehyde,  which  materially  lessens  dan- 
ger to  the  pulp  and  pain  from  its  application. 


TREATMENT    OF    HYPERSENSITIVE    DENTINE  201 

Local  Anesthetics  and  Anodynes. 

Novocain  stands  first  as  a  local  anesthetic  to  desensitize  dentine. 
The  methods  of  using  novocain  for  sensitive  dentine  are  slow  absorp- 
tion and  injection  by  pressure,  in  the  tooth  and  hypodermically.  (See 
Chapter  XLII.) 

The  Slow  Absorption  Method  is  best  practiced  by  putting  into 
the  cavity  a  one-sixth  grain  tablet  of  novocain;  over  this  place  a 
pledget  of  cotton  which  has  been  moistened  with  the  normal  salt 
solution,  and  proceed  to  fill  tooth  with  stopping,  seeing  the  cavity 
again  for  excavation  in  twenty-four  or  forty-eight  hours. 

Pressure  Anesthesia  of  the  dentine  may  be  accomplished  in  two 
general  ways.  The  dentine  should  be  thoroughly  sterilized,  the  above 
application  of  novocain  in  the  normal  salt  solution  made,  over  this 
a  piece  of  unvulcanized  rubber  placed,  and  all  crowded  into  the 
cavity  with  as  much  force  as  the  patient  will  permit. 

High  Pressure  Syringes  are  sometimes  of  service  to  simply  de- 
sensitize the  dentine,  but  their  use  for  this  alone  has  never  become 
general  practice,  due  to  the  danger  of  pulp  infection. 

Phenol  (known  to  the  laity  as  carbolic  acid)  is  a  valuable  rem- 
edy for  hypersensitive  dentine,  as  well  as  for  materially  lessening 
the  pain  caused  by  the  blast  of  air  from  the  chip  blower,  and  should 
never  be  forgotten  when  the  patient  complains  of  the  air  causing 
pain.  In  addition  to  coagulating  the  albumen  in  the  tubuli  it  possesses 
analgesic  properties. 

The  Method  of  Using  Phenol  for  sensitive  dentine  is  to  carefully 
desiccate  the  dentine  with  alcohol  and  warm  air,  applying  a  pledget 
of  cotton  saturated  with  the  phenol,  directing  thereon  a  current  of 
warm  air  until  the  cotton  is  nearly  or  quite  dry.  This  should  be 
repeated  as  often  as  the  ease  demands. 

Oil  of  Cloves  is  a  valuable  remedy  in  this  respect  and  tlie  method 
of  its  use  is  the  same  as  that  just  described  for  phenol. 

Oil  of  Cloves  and  Phenol  Combined,  as  two  parts  phenol  and  one 
part  oil  of  cloves,  applied  to  the  dry  open  cavity  and  evaporated 
therefrom,  with  the  current  of  warm  air,  is  more  effective  than  either 
the  phenol  or  oil  of  cloves  alone.  This  method  with  these  agents 
has  to  recommend  it  the  fact  of  being  a  good  means  of  sterilization, 
it  is  a  pulp  pacifier  in  deep  cavities,  and  no  injury  can  reach  the 
pulp,  provided  the  temperature  of  the  current  of  warm  air  is  not  too 
high. 


202  OPERATIVE  DENTISTRY 

Through  the  General  System. 

Potassium  Bromide  in  5-grain  doses  three  times  a  day  for  forty- 
eight  hours  previous  to  a  sitting  at  the  dentist's  will  do  much  to 
remove  the  nervousness  caused  by  the  fear  of  the  intended  visit  and 
serve  to  minimize  the  pain  to  be  endured. 

Nitrous  Oxide  when  properly  administered  is  of  great  value  and 
efficiency.  It  should  be  combined  with  oxygen  or  compressed  air  in 
proper  proportions.  So  combined  and  administered,  it  may  be  given 
for  a  protracted  period,  long  enough  to  prepare  one  or  more  sensi- 
tive cavities  without  pain  to  the  patient  and  in  most  cases  with  no 
danger  to  health  or  life. 

Somnoforme.  Somnoforme  when  administered  through  a  special 
apparatus  is  one  of  our  most  efficient  means  of  rendering  the  patient 
semi-conscious  and  practically  immune  from  any  pain  of  dental  opera- 
tions. In  the  administering  of  this  as  well  as  other  anesthetics  for 
analgesia,  all  of  the  rules  pertaining  to  the  administration  of  the 
same  anesthetic  for  major  operations  must  be  observed  as  the  same 
danger  to  life  exists. 

Chloroform  Slowly  Administered  and  only  to  the  first  stage  of 
anesthesia  is  a  most  valuable  means  of  dealing  with  severe  cases. 
This  is  particularly  true  of  the  A.  C.  E.  mixture  (alcohol,  chloroform 
and  ether,  equal  parts).  The  primary  effect  is  to  paralyze  the  sen- 
sory nerves,  as  the  ends  of  the  fingers,  the  skin  and  mucous  mem- 
brane in  general  and  this  is  true  in  the  tooth's  pulp  with  the  fibers 
ending  in  the  odontoblastic  layer  of  cells  wherein  abundant  sensitive- 
ness has  been  developed. 

The  Method  of  Administration  is  quite  the  same  as  that  for  any 
other  operation  except  that  it  is  not  carried  past  the  first  stage  of 
anesthesia.  All  that  part  of  the  preparation  of  the  cavity  not  pro- 
ducing pain  is  carried  out,  after  which  the  dental  chair  is  tipped 
back  to  as  recumbent  a  position  as  will  admit  of  operating.  A  nap- 
kin is  then  spread  over  the  lower  part  of  the  face,  leaving  the  eyes 
uncovered.  The  chloroform,  or  better  the  A.  C.  E.  mixture,  is  added, 
first  slowly  a  drop  or  two  at  a  time  and  carried  to  the  point  where 
the  patient  feels  a  tingling  sensation  in  the  finger  tips  or  expresses 
the  fact  that  they  begin  to  feel  the  effects  of  the  drug.  The  anes- 
thetic should  never  be  crowded  or  confined  while  the  patient  can 
smell  the  chloroform,  but  can  be  pushed  more  rapidly  when  the  ol- 
factory nerves  have  been  paralyzed,  so  that  the  sense  of  smell  is  lost, 
and  it  is  not  long  thereafter  until  the  dentine  can  be  excavated  pain- 
lessly.   As  soon  as  the  operator  begins  to  operate  the  assistant  should 


TREATMENT    OF    HYPERSENSITIVE    DENTINE  203 

hold  to  the  nostrils  a  large-moiithed  bottle  of  the  anesthetic  to  pro- 
long the  stage  of  anesthesia  reached.  At  no  time  should  the  patient 
be  suffieiently  under  the  influenee  of  the  anesthetic  to  be  unable  to 
converse  coherently  or  intelligently  answer  the  questions  put  to  him. 

It  must  be  remembered  that  any  anesthetic  has  its  dangers,  par- 
ticularly when  its  use  is  abused,  but  the  above  method  can  be  recom- 
mended as  comparatively  safe.  One  writer  reports  its  use  in  over 
20,000  cases  without  ill  effects.  It  is  true  that  a  large  per  cent  of 
the  cases  wherein  death  has  resulted  from  the  administration  of 
chloroform  or  ether  have  occurred  in  the  first  few  breaths,  as  we 
believe  due  to  a  strong  mixture  used  at  first  or  before  the  nerve 
filaments  of  the  air  passages  have  been  anesthetized. 

If  a  few  breaths  administered  as  alcove,  by  the  open  method,  proved 
fatal,  literature  would  be  replete  with  long  accounts  of  druggists, 
jihysicians,  dentists  and  others  having  met  death  by  smelling  of 
opened  bottles  of  these  drugs. 

Rapid  Breathing  as  a  means  of  producing  periphei-al  anesthesia 
should  receive  consideration,  not  only  for  hypersensitiveness  of  the 
dentine  but  for  other  minor  dental  operations  as  the  use  of  hypo- 
dermic needle,  lancing  of  abscesses  and  extraction  of  teeth.  The 
anesthetic  elTect  is  brought  about  by  superoxidization  within  the  tis- 
sues caused  ])y  charging  the  blood  with  an  abundance  of  oxygen. 

This  Method  Is  Employed  by  instructing  the  patient  to  take 
deep,  long  1)reaths  as  rapidly  as  possible  and  continue  the  same  until 
a  sense  of  dizziness  is  brought  on,  when  from  thirty  to  sixty  seconds 
of  the  anesthetized  condition  will  be  found  available  for  operating. 

Mechanical  Conditions. 

The  Mechanical  Conditions  under  which  the  cutting  of  dentine 
is  done  is  a  great  factor  in  the  amount  of  pain  produced. 

Sharp  instruments  which  cut  without  pressure  upon  the  contents 
of  the  tubuli  cause  much  less  pain  than  dull  ones  even  with  hand 
in.struments.  With  rapidly  revolving  engine  burs  this  is  also  true 
to  say  nothing  of  the  heat  produced  by  the  friction  caused  by  rub- 
bing surfaces  which  are  worn  away  rather  than  cut,  which  is  the 
chief  sf)urr'o  of  p;iin  in  the  use  of  burs. 

The  Cutting  Should  Be  Done  as  much  as  ])ossil)k'  a1  a  right  angle 
to  the  long  axis  of  the  tubules  rather  than  to  follow  their  course  with 
pressure  towards  the  pulp  or  in  a  line  with  their  long  axis. 


CHAPTER  XXXIV. 
PROTECTION  OF  THE  VITAL  PULP. 

The  Normal  Pulp  has  no  tactile  sense,  neither  is  it  responsive  to 
thermal  changes  even  though  they  vary  considerably  from  the  body 
temperature. 

When  Robbed  of  Its  Normal  Covering  and  Protection  the  re- 
verse of  the  above  conditions  quickly  develops.  The  sense  of  touch 
becomes  very  acute  and  any  contact  with  foreign  substances  causes 
great  pain.  This  is  best  illustrated  when  a  tooth  is  broken  through 
its  crown  by  a  blow,  thus  exposing  the  pulp.  At  first  the  pulp  may 
be  touched  with  the  finger  or  an  instrument  without  the  knowledge 
of  the  patient  but  in  a  very  few  minutes  the  same  will  cause  unbear- 
able pain.  Also  at  first  the  cold  air  does  not  affect  the  pulp,  but,  co- 
incident with  the  development  of  the  tactile  sense,  comes  a  repug- 
nance to  the  cold. 

The  Chief  Idiosyncrasy  of  the  Pulp  is  its  response  to  thermal 
changes  and  especially  to  cold,  when  these  changes  are  rapid  or  the 
pulp  is  in  any  way  hyperemic.  A  normal  pulp  will  tolerate  with- 
out response  quite  a  range  of  temperature  when  the  change  is  brought 
about  slowly.  This  is  generally  the  case  when  the  pulp  is  covered 
with  the  full  crown  of  the  tooth.  But  when,  through  decay  or  other 
causes,  this  covering  is  all  or  partially  lost,  the  changes  are  so  rapid 
that  the  peculiar  responsive  features  spoken  of  are  developed. 

The  Recuperative  Powers  of  the  Pulp  are  very  slight,  the  least 
of  the  soft  tissues  of  the  body,  as  it  will  regain  a  healthy  condition 
from  only  the  initial  stages  of  disease.  It  will  many  times  make 
a  feeble  effort  to  protect  itself  when  the  irritation  is  mild  by  filling 
up  the  dental  tubuli  with  calcic  matter  or  a  secondary  construction 
of  dentine,  through  the  activity  of  its  odontoblastic  layer  of  cells. 
Even  this  reparative  process  must  not  be  vigorously  inaugurated  or 
the  death  of  the  pulp  will  result,  proving  that  these  reparative  meas- 
ures on  the  part  of  the  pulp  are  pathological,  rather  than  physio- 
logical in  nature. 

The  Protection  of  the  Pulp  from  its  greatest  enemy,  sudden 
thermal  changes,  is  most  essential  and  as  most  of  our  desirable  fill- 
ing materials  are  good  conductors  of  heat  and  cold  it  becomes  neces- 
sary to  place  some  substance  which  is  a  poor  conductor  between  the 
filling  and  the  dentine,  this  operation  being  termed  ''capping  the 
pulp." 

204 


PROTECTION    OF    THE    VITAL    PULP  205 

The  Indications  for  Pulp  Protection  are  not  al^^■ays  clear,  but  will 
involve  a  consideration  of  the  age  of  the  patient,  extent  of  loss  of 
dentine,  location  of  the  cavity  in  the  tooth,  location  in  the  mouth, 
length  of  time  the  pulp  has  been  exposed,  the  stage  of  hyperemia, 
the  general  health  of  the  patient  and  the  possibilities  of  pulp  infec- 
tion. 

The  Ag-e  of  the  Patient  has  a  bearing  on  the  successful  issue  of  a 
conservative  treatment,  as  the  teeth  of  the  young  are  more  easily 
saved  from  further  irritation  through  capping  than  are  the  teeth  of 
those  past  middle  age,  while  at  the  same  time  they  demand  capping 
more  frequently  under  the  same  conditions.  Again,  the  pulp  should 
be  saved  if  possible  until  the  teeth  are  fully  formed,  and  many  times 
the  teeth  of  the  younger  patients  are  badly  decayed  and  the  pulp 
in  great  danger  before  the  teeth  are  complete,  hence  if  the  pulp  can 
be  conserved  and  devitalization  avoided,  it  is  of  great  good  to  the 
patient. 

In  Advanced  Age  the  apical  openings  become  smaller  and  many 
become  much  contracted,  barely  accommodating  the  vessels  with  a 
normal  floAv  of  blood  so  that  a  very  slight  congestion  may  cause  death 
from  strangulation  or  gangrene. 

When  a  Large  Amount  of  Dentine  Has  Been  Lost,  even  though 
the  pulp  as  yet  seems  normal,  it  is  safe  practice  to  avoid  the  plac- 
ing of  the  best  conductors,  as  gold  or  amalgam,  in  close  proximity 
to  the  pulp  as  repeated  shocks  to  the  pulp  through  the  filling  from 
thermal  changes  may  bring  on  hyperemia  of  that  organ.  In  the  use 
of  phosphate  of  zinc  cement  in  such  cases,  there  should  be  an  inter- 
vening media  to  prevent  the  irritating  effect  of  phosphoric  acid. 

The  Location  of  the  Cavity  is  a  factor  in  the  demands  for  pulp 
protection,  as  well  as  the  probability  of  success  in  extreme  cases. 
The  first  portions  of  the  pulp  to  show  hyperemic  conditions  are  those 
nearest  to  the  point  of  irritation.  These  congestions  are  more  dan- 
gerous when  they  appear  in  the  body  of  the  pulp,  as  they  do  where 
decay  approaches  the  pulp  in  the  gingival  third.  Hence,  when  a 
pulp  is  nearly  exposed  in  this  location  it  demands  greater  protection 
and  is  at  the  same  time  harder  to  save  than  when  the  horns  of  the 
pulj)  ai-e  involved. 

The  Location  of  the  Tooth  sliould  l^e  considered.  Autei-ioi-  teeth 
are  subjcf-t  to  greater  oxtreiiics  of  heat  and  cold  than  are  the  molars, 
hence  the  demand  for  preventive  protection  with  the  anterior  teeth 
should  be  rcnieinljored.  At  the  same  time  their  exposed  position 
makes  pul|>-capping  more  hazardous  and  it  should  be  practiced  with 
great  care  in  this  location.     Again,  less  risk  should  be  taken  in  the 


206  OPERATIVE  DENTISTRY 

capping  of  pulps  in  the  anterior  portion  of  the  mouth  as  it  is  better 
to  remove  a  number  of  questionable  pulps  than  to  have  one  die  in 
the  tooth  with  its  consequent  discoloration. 

The  Length  of  the  Time  the  pulp  has  been  exposed  to  the  irritat- 
ing influences  is  to  be  taken  into  account  as  the  shorter  the  time  of 
exposure,  the  greater  the  probabilities  of  success  in  capping. 

The  Stage  of  Hyperemia  should  be  a  safe  criterion  where  there 
are  actual  pulp  complications,  as  there  will  be  in  almost  every  deep- 
seated  cavity.  In  active  hyperemia,  from  causes  other  than  bacteria, 
it  is  safe  to  protect  the  pulp  from  futui'e  irritation  and  insure  its 
conservation.  However,  when  the  symptoms  of  passive  hyperemia 
have  developed  it  is  not  safe  practice  to  attempt  to  restore  the  pulp 
to  normal  and  expect  permanency. 

The  Symptoms  of  Active  Hyperemia  when  the  pulp  demands 
protection  and  success  may  be  expected  are : 

First — When  the  excavated  cavity  exposed  to  the  air  causes  a  con- 
tinued pain  not  of  a  throbbing  nature  and  the  condition  is  relieved 
by  packing  the  cavity  with  dry  cotton. 

Second — When  a  blast  of  air  from  the  chip  blower  causes  a  quick, 
sharp,  shooting  pain  which  subsides  as  quickly  as  it  came. 

TTiird — When  the  pulp  shows  the  power  of  accommodation  as  evi- 
denced by  tolerating  a  draft  of  cold  air  when  the  same  is  gradually 
applied. 

Fourth — When  it  is  improbable  that  the  pulp  has  become  infected. 

Pulps  Infected  With  Bacteria  should  be  extirpated  as  too  large 
a  percentage  of  those  exposed  and  capped  die  and  thereby  bring  re- 
proach upon  dentistry  in  general  and  chagrin  to  the  careful  operator. 

The  time  was  when  the  profession  attempted  to  conserve  all  por- 
tions of  the  pulp  found  to  be  vital,  even  to  amputating  the  coronal 
portion  and  leaving  intact  the  vital  stumps.  However,  this  was  in 
the  days  of  imperfect  root  canal  treatment  and  filling  and  about  as 
many  abscesses  followed  one  kind  of  treatment  as  the  other.  But 
at  the  present  time  the  removal  of  a  pulp  is  attended  with  such  uni- 
versal success  that  the  capping  of  exposed  pulps,  in  general,  is  un- 
warranted, as  most  pulps  are  infected  at  the  time  of  exposure.  Even 
in  the  case  of  an  accidental  exposure  in  the  preparation  of  a  cavity 
neither  cavity  nor  instruments  are  surgically  sterile. 

The  General  Health  of  the  Patient  must  be  considered  when 
choosing  between  the  conservative  or  radical  treatment  of  the  pulp. 
With  the  same  conditions  presented,  the  pulps  in  the  teeth  of  the  an- 
emic patient,  those  wherein  the  vital  processes  are  at  low  ebb,  or  the 


PROTECTION    OF    THE    VITAL    PULP  207 

elimination  of  the  vital  ash  is  imperfect  and  cell  metabolism  is  defi- 
cient, protective  means  of  conservation  are  more  imperative,  while  at 
the  same  time  less  risk  should  be  taken  in  questionable  cases. 

With  Robust  and  Particularly  Plethoric  Patients,  all  inflamma- 
tory processes  run  a  rapid  and  riotous  course,  and  when  the  pulp 
has  taken  on  any  stage  of  hyperemia  changes  towards  dissolution  are 
of  rapid  succession. 

In  Deep-Seated  Cavities  it  is  not  unlikely  that  the  thin  layer  of 
the  dentine  covering  the  pulp  is  infected  and  the  pulp  should  be 
protected  from  the  invasion  by  the  thorough  disinfection  of  the  over- 
lying dentine  by  medication,  previous  to  filling  as  well  as  placing 
next  to  the  dentine  in  question  and  under  the  filling  a  permanent 
dressing  which  will  exert  a  mildly  antiseptic  influence  for  some  time 
following  the  operation. 

The  Requirements  of  the  Materials  Used  in  Protective  Pro- 
cedures Are: 

First — That  they  shall  be  poor  conductors  of  heat  and  cold. 

Second — That  they  shall  be  non-changing  in  character,  both  as  to 
consistency  and  bulk. 

Tliii'd — That  they  have  no  action  upon  the  pulp. 

Fourtli — That  they  may  be  introduced  into  deep  seated  cavities 
without  pressure. 

The  Materials  Advocated  for  This  Purpose  Are  Numerous  and 
the  market  is  flooded  with  preparations  of  a  secret  nature  which  are 
warranted  to  save  the  pulp  in  almost  any  stage  of  dissolution,  but 
the  operator  who  pins  his  faith  to  such  slipshod  methods  will  sooner 
or  later  find  that  he  has  been  duped  and  his  grief  is  measured  by 
the  extent  to  which  he  has  employed  these  cure-all  methods. 

There  Are  Four  Distinct  Classifications  Avherein  success  may  be 
expected  in  methods  of  pulp  protection.  The  treatment  of  each 
class  is  here  given. 

First  Class.  In  the  Progressive  Stage  of  Caries  ^\•hcrein  Init  lit- 
tle dentine  has  l)een  lost,  yet  a  blast  of  air  from  the  chip  blower 
causes  a  fiuick,  sharj)  pain,  passing  off  as  soon  as  the  draft  of  air 
is  checked,  we  find  the  simplest  form  demanding  protective  measures. 
This  is  the  class  most  often  neglected  hy  the  operator  and  many 
times  irrei)arable  injury  is  done  a  pulp  by  placing  in  such  a  cavity 
a  filling  of  high  conductivity,  such  as  gold  or  amalgam.  The  patient 
often  believes  that  "cold  water  leaks  in  about  the  filling"  and  may 
visit  another  dentist  thinking  that  he  has  a  poor  piece  of  dentistry, 
and  the  patient  may  be  lost  to  an  otherwise  good  opei'ator,  all  through 
the  neglect  of  what  may  appear  to  the  operator  as  a  trivial  matter. 


208  OPERATIVE   DENTISTRY 

The  Treatment  of  the  First  Class  is  the  thorough  dismfection 
and  then  the  application  of  phenol,  full  strength,  for  a  few  seconds, 
when  the  cavity  should  be  dried  and  it  will  be  found  unaffected  by 
the  blast  of  air  from  the  chip  blower.  The  change  is  brought  about 
by  the  superficial  coagulation  of  the  albumen  in  the  exposed  ends 
of  the  dental  tubuli  which  renders  them  non-conductive. 

Second  Class.  If,  after  one  or  two  applications  of  the  phenol  as 
above,  the  distress  from  the  blast  of  air  is  not  relieved,  or  if  the 
pain  is  continuous  while  the  surface  of  the  cavity  is  exposed  to  the 
air  it  is  probably  of  the  second  class  as  met  with  in  the  nearer  ap- 
proaches to  the  pulp.  This  class  of  cases  demands  a  media  interven- 
ing the  dentine  and  the  filling. 

The  Treatment  in  the  Second  Class  is  as  follows :  Moisten  the 
cavity  with  phenol  and  evaporate  to  comparative  dryness.  Then 
paint  the  entire  dentinal  walls  with  a  cavity  varnish  composed  of 
copal  and  gum  dammar  in  alcohol  and  ether  solution.  Such  a  prep- 
aration can  be  had  at  the  dental  depots  or  it  can  be  prepared  by  the 
druggist.  This  should  be  thin  and  spread  evenly,  applying  one,  two 
or  three  coats  and  drying  with  a  draft  of  air  from  the  chip  blower 
after  each  coat.  When  the  varnish  is  entirely  hardened  the  filling 
may  be  placed. 

Third  Class.  In  the  deep-seated  stage  of  caries,  where  large 
quantities  of  dentine  have  been  lost,  even  though  the  pulps  may 
seem  to  be  protected  by  secondary  dentine  that  is  much  retracted, 
it  is  not  safe  to  place  a  metal  filling  directly  on  the  overlying  den- 
tine. The  lost  tooth  structure  should  in  a  measure  be  replaced  with 
a  material  which  is  not  a  better  conductor  of  thermal  changes  than 
dentine.  This  should  be  neutral  as  far  as  irritating  properties  are 
concerned,  non-changing  and  should  resist  the  force  necessary  to 
properly  introduce  the  intended  filling. 

The  Treatment  in  the  Third  Class  is  as  follows :  Phenolize  and 
dry.  Varnish  with  the  above  cavity  varnish  and  dry.  Flow  over 
the  dentine,  covering  most  if  not  all  of  the  axial  or  pulpal  wall,  or 
both,  according  to  the  class  of  cavity  being  treated,  a  thin  layer  of 
oxyphosphate  of  zinc  cement,  being  careful  not  to  include  thereunder 
any  air  bubbles;  also  apply  without  pressure.  Then  allow  this  to 
set  to  complete  hardness,  when  the  filling  may  be  completed.  In  the 
three  classes  given  above  it  will  be  noted  that  coagulation  of  the 
protoplasm  in  the  exposed  ends  of  the  tubuli  was  the  first  step.  This 
is  good  practice  from  the  fact  that  this  layer  of  coagulum  is  the 
least  irritant  to  the  remaining  protoplasm  of  anything  of  which  we 
have  knowledge.     Phenol  is  very  limited  in  the  extent  of  its  action 


PROTECTION'    OF    THE    VITAL    PULP  209 

and  this  layer  of  coagulation  is  very  thin.  Again,  with  this  third 
class,  it  will  be  noted  that  in  addition  to  the  nse  of  the  phenol  the 
cavity  is  given  a  coat  of  varnish  before  applying  the  oxyphosphate 
of  zinc  cement.  This  procedure  is  to  prevent  the  irritating  effects 
of  the  phosphoric  acid,  particularly  while  the  cement  is  setting. 
Again,  should  the  zinc  contain  any  impurities  their  action  on  the 
pulp  is  prevented.  One  of  the  impurities  of  zinc  is  arsenic  and  some 
cements  are  thought  to  contain  traces  of  this  devitalizing  agent.  The 
cavity  varnish  given  above  is  quite  impervious  to  this  element  when 
it  has  been  thoroughly  hardened,  a  fact  which  should  not  ])e  over- 
looked when  it  is  desired  to  prevent  the  action  of  arsenic  trioxide  in 
a  particular  direction  in  a  dental  wall. 

Fourth  Class.  In  deep-seated  cavities  where  there  is  a  slight 
pulp  complication  from  thermal  shock  and  where  the  thin  overlying 
layer  of  dentine  is  probably  infected  to  some  depth  and  more  deeply 
affected  in  the  process  of  caries,  the  dentine  should  be  subjected  to 
quite  a  continued  disinfecting  process  and  a  portion  of  the  lost  den- 
tine restored  with  a  non-conducting  material  to  shield  the  pulp  from 
sudden  thermal  changes. 

The  Treatment  in  the  Fourth  Class  of  cases  is  as  follows:  The 
cavity  should  be  flooded  with  a  non-irritating  antiseptic,  as  campho- 
phenique,  pure  beeehwood  creosote  or  oil  of  cloves.  If  sealed  in  the 
cavity  for  twenty-four  hours  the  result  will  l)e  much  better.  The 
cavity  should  be  then  wiped  dry  with  absorbent  cotton  and  a  thin 
paste  of  a  cement  containing  sulphate  of  zinc  spread  over  the  den- 
tine overlying  the  pulp.  This  paste  should  be  tliiii  enough  to  flow 
to  position  when  coaxed  with  a  small  in.strument,  yet  thick  enough 
to  prevent  its  spreading  to  surfaces  not  needed.  Over  this  spread 
a  layer  of  oxyphosphate  of  zinc  cement  and  jilldu  this  to  set  hard  be- 
fore completing  the  filling. 

In  very  questionable  cases,  the  eiitire  cavity  may  be  completed 
with  the  cement  and  the  patient  dismissed  for  six  months,  at  the  end 
of  which  time,  if  the  pulp  is  found  to  be  normal,  a  portion  of  the  ce- 
ment may  be  removed  and  replaced  with  a  more  permanent  ma- 
terial. 

Pulp  Preservers  and  So-Called  Mummifiers  should  be  avoided. 
Even  their  name  is  misleading  and  such  i)]'epai-ations  arc  used  with- 
out permanent  success  in  the  majoi-ity  of  ca.ses.  Their  use  simply 
proclaims  their  users  as  un.skilled  laggards  who  will  accept  an  un- 
certainty to  avoid  a  little  honest  labor  in  pulp  extirpation  and  root 
filling.     The  entire  procedure  is  diabolical  and  cannot  be  condemned 


210  OPERATIVE    DENTISTRY 

in  too  severe  terms  as  a  retrogression  in  dentistry,  unskilled  in  prin- 
ciple and  unwarranted  in  practice. 

Gutta-Percha  as  a  Protecting  Covering  is  not  a  success  from  the 
fact  of  its  great  range  of  contraction  and  expansion  under  varying 
thermal  changes.  When  enclosed  under  a  perfectly  tight  and  un- 
yielding filling,  as  all  fillings  should  be,  the  change  in  bulk  must 
have  a  piston-like  effect  upon  the  contents  of  the  dental  tubuli  result- 
ing in  continued  irritation. 


CHAPTER  XXXV. 
PULP  DEVITALIZATION  AND  REMOVAL. 

The  Reason  for  Devitalization  and  Removal  of  a  pulp  is  its  pres- 
ent unhealthy  condition  or  when  its  future  health  is  in  danger,  on 
account  of  environment  in  the  way  of  dental  operations. 

There  Are  Two  General  Causes  of  diseased  pulps. 

First.  That  succession  of  tissue  changes  which  has  its  origin  in 
active  hyperemia  and  its  end  in  death  due  to  the  presence  of  bacteria 
or  their  products — inflammation. 

Second.  Reparative  congestion,  due  to  traumatic  injury,  abnor- 
mal thermal  stimuli,  lack  of  normal  thermal  stimuli  and  peripheral 
nerve  irritation. 

Bacteria  and  Their  Products  may  enter  the  pulp  tissue  either 
through  a  loss  of  its  normal  covering,  the  dentine,  as  in  the  case  of 
deep-seated  caries,  or  through  the  general  circulation  by  way  of  the 
apical  foramen,  as  in  pyorrhea  alveolaris,  or  in  other  pus  conditions 
in  close  proximity  to  the  pulp  vessels.  We  have  no  means  of  know- 
ing that  a  pulp  thus  invaded  has  recovered,  while  we  have  complete 
proof  of  their  subsequent  death  from  this  cause,  hence  devitaliza- 
tion is  indicated  as  soon  as  diagnosis  is  clear. 

The  Removal  of  the  Cause  in  reparative  congestion  of  the  pulp 
will  genei-ally  suffice  to  save  the  pulp  from  further  destruction  pro- 
vided the  intervention  is  in  the  stage  of  active  hyperemia. 

The  Traumatic  Injuries  most  common  in  the  production  of  pulp 
congestion  are  blows  upon  the  teeth  either  through  accident  or  ex- 
cessive malleting  in  dental  operations;  rapid  movement  by  the  ortho- 
dontist; abnormal  stress  in  occlusion  or  articulation;  malocclusion 
and  abnormal  movement  of  the  tooth  in  its  alveolus  made  possible 
by  the  loss  of  supporting  structures. 

Abnormal  Thermal  Stimuli  is  a  most  potent  factor  in  producing 
pulp  congestion.  The  pulp  is  particularly  and  peculiarly  susceptible 
to  thermal  changes  and  this  idiosyncrasy  is  very  rapidly  magnified 
as  the  stages  of  congestion  progress. 

The  Reason  for  Abnormal  Thermal  Changes  reaching  the  pulp 
is  the  loss  of  its  natui'al  covering,  the  dentiiie  and  enamel,  through 
caries,  erosion,  abrasion  oi"  dental  operations  as  well  as  the  denuding 
of  the  root  by  a  recession  or  loss  of  the  sub-gingival  structures. 

Lack  of  Normal  Thermal  Stimuli  will  induce  a  stagnated  cii-cu- 
lation  with  a  sequela  of  degtinerative  changes  within  the  pulp  tissues, 

211 


212  OPERATIVE    DENTISTRY 

resulting,  many  times,  in  the  death  of  that  organ.  While  the  pulp 
is  profoundly  affected  by  abnormal  exposure  to  heat  and  cold  it  is 
eminently  essential  to  its  normal  physiological  existence  that  it  re- 
ceive the  stimulating  effects  of  the  ranges  of  temperature  usually 
found  in  food  and  drink  while  covered  with  the  entire  tooth. 

Peripheral  Nerve  Irritation  may  bring  about  reparative  conges- 
tion within  the  pulp  causing  excessive  tissue  waste  and  a  precipita- 
tion of  lime  salts  within  the  pulp.  There  are  two  classes  of  these 
deposits,  known  as  calcific  degeneration  and  pulp  nodules,  the  latter 
being  the  sequela  of  peripheral  irritation,  while  calcific  degeneration 
is  the  result  of  little  local  passive  hyperemias  with  its  cause  related 
to  abnormal  thermal  changes. 

The  Irritation  May  Be  in  the  terniinal  fibers  of  the  nerves  A^-ithin 
the  pulp  where  the  nodules  are  found,  or  in  an  approximating  toothy 
or  in  a  tooth  in  the  same  lateral  half  of  the  jaw  or  face.  Cases  are 
reported  where  it  is  evident  that  the  cause  is  even  more  remote  than 
has  been  stated,  it  being  a  local  expression  of  a  general  neurotic  con- 
dition. 

The  Requirements  of  a  Devitalizing  Agent  are : 

First.  That  the  present  and  future  health  of  adjacent  tissues  be 
maintained. 

Second.     That  it  act  painlessly. 

TMrd.     That  the  dentine  is  not  discolored. 

Fourtli.  That  devitalization  be  accomplished  promptly,  resulting 
in  a  saving  of  time  to  both  the  patient  and  operator. 

The  Methods  of  Pulp  Devitalization  practiced  at  this  time  are 
two:  Surgical  amputation  while  anesthetized  and  poisoning  by  the 
application  of  arsenic  trioxide. 

To  Determine  the  Method  to  employ  in  any  given  case  requires 
an  understanding  of  the  pulp  presented,  its  immediate  surroundings, 
and  results  sought.  Also  the  time  at  the  disposal  of  patient  and 
operator.  While  each  of  the  two  methods  has  its  advantages,  either 
can  be  so  used  as  to  meet  the  requirements  of  a  satisfactory  means  of 
devitalization. 

Anesthetization  of  the  Pulp  is  accomplished  by  forcing  into  the 
pulp  either  a  solution  of  cocaine  hydrochloride  or  novocain  popularly 
known  as  ''pressure  anesthesia." 

Anesthetization  Is  Indicated: 

First.    When  it  is  desired  to  remove  a  normal  pulp. 

Second.  When  slight  exposure  of  the  pulp  exists  which  has  not 
yet  reached  the  stage  of  passive  hyperemia. 


PULP    DEVITALIZATION    AND    REMOVAL  213 

Third.  Pulps  whose  circulatory  system  is  active,  but  whose  ner- 
vous system  is  either  deficient  in  development  or  is  in  the  stages  of 
neuroparalysis.  Access  to  the  tooth  is  a  factor  to  be  considered  and 
will  result  in  the  more  frequent  use  of  this  method  with  the  anterior 
teeth.  The  possibility  of  securing  a  sterile  field  of  operation  must 
be  considered  as  an  advantage. 

The  Technic  of  the  Operation  wliere  a  cavity  exists  is  as  follows : 
Apply  the  rubber  dam.  Excavate  the  affected  dentine.  Sterilize  the 
remaining  cavity.  Place  in  the  cavity  over  the  pulp  a  small  pellet 
of  cotton  saturated  Avith  either  cocaine  or  novocain.  Apply  over 
this  a  piece  of  unvulcanized  rubber  which  will  approximately  fill  the 
cavity  and  with  l)lunt  instruments,  as  amalgam  packers,  gently  force 
the  mass  in  the  direction  of  the  pulp.  It  is  essential  that  the  rubber 
first  come  into  contact  with  the  cavity  margins  at  all  points,  or  the 
fluid  will  not  be  confined  and  its  escape  renders  the  attempt  a  fail- 
ure. If  the  first  pressure  of  the  confined  solution  upon  the  pulp 
causes  pain  the  operator  should  stop  increasing  the  pressure,  but 
hold  the  advantage  gained  by  not  releasing  the  pressure  already  ap- 
plied, when,  after  Avaiting  a  minute  or  two,  the  pressure  may  be  in- 
creased and  finally  the  rubber  can  be  kneaded  into  the  cavity  with 
considerable  force.  Sometimes  one  application  thus  made  will  com- 
pletely anesthetize  a  pulp.  However,  other  eases  Avill  require  two 
or  more  applications.  BetAveen  such  applications  the  dentine  should 
be  removed  from  over  the  pulp  to  complete  exposure  Avhere  this  can 
be  done  Avithout  undue  pain  to  the  patient. 

When,  after  tAvo  or  three  attempts  of  the  above  method  there  seems 
to  be  no  effect  obtained,  it  is  generally  best  for  both  patient  and  oper- 
ator to  i-esort  to  the  application  of  arsenic,  unless  the  case  is  suited 
to  favor  the  use  of  the  high  pressure  syringe. 

The  High  Pressure  Syringe  is  of  service  Avhei-e  no  exposure  ex- 
ists, and  Avhere  the  necessary  puncture  for  the  introduction  of  the 
gyringe  point  can  be  included  in  the  filling,  or  Avhere  the  croAAai  is 
to  give  place  to  an  artificial  one  as  an  abutment  for  a  bridge.  The 
method  has  to  recommend  it  speed,  a  certainty  of  preserving  the 
color  and  is  generally  accomyilishod  Avith  little  ov  no  pnin  to  the  pn- 
tient. 

The  Technic  in  Its  Use.  To  Ihc  prescription  given  for  the  open 
cavity  add  fift('(!n  drojjs  of  distilled  water  and  load  the  syringe,  see- 
ing that  all  joints  are  screwed  uj)  tight.  Select  a  point  of  direct 
access  either  on  the  dentinal  walls  or  it  may  be  on  Ihc  cxtei-nal  onaiiK'l 
surface,  preferably  in  the  gingival  third  of  the  toolh.  and  drill  a 
hole  directly  towards  the  f)iilp  one  millimeter  in  depth  and  as  much 


214  OPERATIVE   DENTISTRY 

farther  as  possible  without  causing  the  patient  pain.  The  drill  used 
should  be  smaller  than  the  syringe  point  that  a  close  fit  to  the  hole 
may  be  secured.  Syringes  are  generally  constructed  so  that  a  drill 
made  by  flattening  a  No.  1-2  round  bur  will  make  a  proper  sized  hole. 
The  syringe  is  then  applied  to  the  opening  with  some  pressure  and 
its  contents  forced  into  the  dentine. 

It  is  essential  that  the  solution  be  perfectly  imprisoned  as  it  re- 
quires high  pressure  to  force  the  anesthetic  through  the  tubuli.  Af- 
ter holding  the  solution  at  high  pressure  in  contact  with  the  dentine 
for  one  or  two  minutes  it  should  be  removed  and  the  drill  applied  to 
the  hole  to  test  its  sensitiveness.  If  desensitized  the  hole  should  be 
carried  close  to  the  pulp  but  not  so  far  as  to  enter  the  chamber.  The 
syringe  should  be  again  applied  and  with  great  care,  as  sudden  force 
may  cause  pain  by  too  rapid  pressure  upon  the  pulp. 

Great  Care  Should  Be  Exercised  when  the  pulp  has  been  thus 
nearly  or  quite  exposed  not  to  force  into  the  pulp  any  considerable 
amount  of  the  anesthetic  as  it  is  carried  or  forced  beyond  the  apical 
foramen,  from  which  no  good  can  result  and  harm  may,  particularly 
if  the  contents  of  an  infected  pulp  are  forced  through  to  the  tissues 
of  the  pericementum. 

Pulp  Extirpation  by  Hypodermic  Injection.  Pulps  may  be  re- 
moved very  quickly  and  without  pain  by  injecting  the  solution  of 
novocain  as  given  for  use  in  extracting  teeth  in  Chapter  XLI. 

If  Correctly  Done  the  Pulp  May  Be  Removed  or  the  tooth  ex- 
tracted painlessly.  Extreme  care  as  to  asepsis  must  be  given.  This 
danger  of  infection  makes  this  method  unsuited  for  general  use,  but 
applicable  to  cases  where  haste  is  imperative  or  where  trouble  is  ex- 
perienced in  the  use  of  pressure  anesthesia  or  arsenic  devitalization. 

The  Removal  of  an  Anesthetized  Pulp  is  accomplished  by  gain- 
ing access  to  the  pulp  chamber  from  a  position  which  will  admit  of 
direct  or  nearly  direct  approach  to  each  of  the  pulp  canals,  and  mak- 
ing the  opening  large  enough  to  admit  light  enough  to  see  either  by 
direct  vision  or  the  image  in  the  mirror,  the  entire  floor  of  the  cham- 
ber. First,  a  smooth  sterile  broach  is  passed  down  each  canal  to  the 
apex  of  the  root,  to  test  the  completeness  of  the  anesthetization.  If 
no  sensation  is  found  the  barbed  broach  is  then  passed  to  the  apex, 
preferably  an  extra  fine  size.  This  should  be  twisted  to  the  right 
about  one  complete  turn  and  then  gently  drawn  from  the  cavity, 
which  should  result  in  the  amputation  and  removal  of  the  entire 
pulp.  This  accomplished,  the  sides  of  the  canal  should  be  rasped 
with  a  barbed  broach  of  a  larger  size  to  remove  any  shreds  which 
may  adhere  to  the  sides  of  the  canals. 


PULP    DEVITALIZATION    AND    REMOVAL 


215 


To  Check  Hemorrhag-e,  should  that  ensue,  Avash  the  chamber  and 
canals  with  cold  water,  dry  as  quickly  as  possible,  flood  cavity  with 
a  drop  of  adrenalin  chloride  and  apply  a  plug  of  dental  rubber, 
pressing  this  into  the  cavity  and  holding  it  for  a  few  minutes.  Re- 
move the  rul)ber  and  wash  again  with  cold  water.  If  hemorrhage 
continues  repeat  holding  the  adrenalin  confined  longer  than  before 
and  applying  a  little  more  force.  Care  should  be  used  in  this  pro- 
cedure as  a  sore  tooth  will  result  when  the  method  has  been  used 
too  vigorously.  Again  thoroughly  bathe  the  canals  with  cold  water 
or  alcohol  and  dry. 

Discoloration  Results  from  allowing  any  blood  to  remain  in  con- 
tact with  the  dentine,  even  though  it  be  only  from  one  treatment  to 
another  as  the  iron  of  the  hemoglobin  is  absorbed  or  forced  into  the 
tubuli  resulting  in  permanent  discoloration.  The  use  of  liydrogen 
dioxide  is  not  good  practice  until  the  blood  has  been  washed  from 
the  dentinal  walls  as  it  oxidizes  the  iron  of  the  hemoglobin  and  dis- 
coloration Avill  result. 

Post-Extirpation  Pains  may  l)e  prevented  by  pumping  into  the 
canals  phenol  with  a  smooth  broach  continuing  this  until  the  nerve 
stump  at  the  foramen  is  bathed  with  this  agent.  This  also  has  the 
effect  of  coagulating  the  mouths  of  the  dental  tubuli,  resulting  in 
sealing  them  to  agents  which  may  cause  discoloration. 

It  Is  the  Best  Practice  to  Dress  the  Canal  or  Canals  for  a  few 
days  with  a  stimulating  anodyne  which  is  at  least  mildly  antiseptic, 
as  the  anesthetizing  of  the  pulp  has  ])ro])al)ly  so  much  affected  the 
tissues  in  the  apical  space  that  there  is  nothing  to  guide  us  in  prop- 
erly filling  the  pulp  canals. 

Immediate  Canal  Filling  in  these  cases  is  sometimes  practiced 
where  lack  of  time  demands  a  hurried  completion  of  the  case  and 
is  quite  successfully  accomplished  where  all  is  just  right.  But  so 
many  times  ideal  conditions  for  canal  filling  are  not  obtainable  that 
its  universal  practice  is  condemned.  However,  if  there  is  to  be  im- 
mediate canal  filling  the  pulp  canals  should  be  l)athed  with  water 
and  dried  with  warm  air,  flooded  with  phenol  and  again  dried,  this 
time  with  the  aid  of  absolute  alcohol,  when  the  canal  filling  may  be 
introduced  as  outlined  in  the  chapter  on  "The  Filling  of  Pulp 
Canals." 

Devitalization  With  Arsenic  Trioxide  is  llic  mctliod  in  most  fre- 
quent  use  and  although  not  always  to  be  i)referred  to  ancstliotiza- 
tion.  it  may  })c  us('<l  in  almost  any  case  with  satisfactory  i-csults. 
Arsenic  Should  Be  Combined  With  Some  Agent  i<.  allay  llic  i)ain 


216  OPERATIVE   DENTISTRY 

caused  by  its  application  as  it  is  a  most  powerful  escharotic  and 
the  clear  arsenic  applied  to  a  pulp  will  often  cause  great  pain.  One 
of  the  most  popular  mixtures  is  here  given: 

Arsenic  trioxide    gr.  v. 

Cocaine gr.  xv. 

Creosote    Q.  S.  ft.  stiff  paste. 

To  this  should  be  added  enough  lamp  black  to  make  the  above  a 
dark  gray  color  so  that  it  will  have  a  contrasting  color  with  that  of 
the  tooth  to  assist  in  placing  it  in  the  exact  location  desired. 

The  Technic  of  its  application  is  as  follows :  The  cavity  should 
be  thoroughly  protected  and  dried,  preferably  under  the  rubber  dam. 
Foreign  matter  should  be  removed  from  the  cavity  and  the  same 
thoroughly  sterilized,  the  softened  dentine  removed  and  the  pulp  ap- 
proached to  as  near  exposure  as  possible  without  causing  the  patient 
pain.  Complete  exposure  is  not  necessary.  Again  sterilize  the  cavity 
and  dry.  Bathe  cavity  with  phenol  and  again  dry.  With  the  enamel 
hatchets  secure  a  definite  cavity  margin,  particularly  if  cavity  is  in 
the  gingival  third.  In  cavities  that  are  sub-gingival  build  in  amal- 
gam as  high  as  the  gum  line  or  at  least  one  or  two  millimeters  high, 
being  sure  not  to  let  this  approach  the  pulp  exposure  or  the  point 
where  the  application  is  to  be  made.  Take,  of  the  above  paste  on 
the  point  of  a  fiat  excavator,  a  quantity  equal  to  about  one-fourth 
the  size  of  a  common  pin  head  and  apply  very  close  to,  but  not  di- 
rectly on  the  exposed  pulp.  By  very  close  is  meant  within  one-half 
millimeter.  Place  over  this  a  piece  of  spunk  the  size  of  a  pin  head, 
or  larger  if  cavity  is  large  and  roomy,  which  has  been  dipped  in 
creosote  and  then  pinched  in  a  napkin  to  dryness,  putting  into  place 
in  such  a  manner  as  not  to  cause  pressure  on  the  pulp.  The  retain- 
ing filling  maj^  now  be  completed  with  amalgam,  cement  or  temporary 
stopping. 

Amalgam  as  a  Retainer  of  arsenic  has  the  advantages  of  making 
a  tight  filling  at  the  margins.  Nothing  will  pass  through  it  and  it 
is  the  most  easily  removed  if  it  is  applied  where  there  are  frail  over- 
hanging enamel  walls  which  a  chisel  will  easily  cleave;  or  if  the 
amalgam  has  been  but  partially  mixed  with  not  enough  mercury, 
resulting  in  a  mealy  filling  or  where  a  great  excess  of  mercury  has 
been  used,  that  is  to  say  where  a  most  poorly  manipulated  amalgam 
has  been  used  resulting  in  its  being  cut  with  a  bur  much  more  easily 
than  cement,  an  advantage  in  cases  where  a  tooth  becomes  sore  to 
percussion. 


PULP    DEVITALIZATION    AND    REMOVAL  217 

Cement  as  a  Retainer  of  arsenic  has  the  advantage  of  settiniz' 
quickly,  thus  removing  the  danger,  in  occlusal  cavities,  of  the  pa- 
tients causing  themselves  pain  by  biting  on  the  fillings  and  produc- 
ing pressure  on  the  pulp.  With  anterior  teeth  it  is  more  sightly 
than  amalgam  or  stopping.  Its  only  disadvantage  is  that  it  some- 
times sets  so  well  that  it  is  hard  to  remove  and  its  adhering  proper- 
ties may  result  in  dragging  or  lifting  the  application  from  its  place- 
ment, during  the  manipulation  of  introduction. 

Temporary  Stopping  as  a  Retainer  of  arse7iic  has  to  recommend 
it  the  ease  of  its  removal  Avith  warmed  instruments  and  especially 
if  its  surface  has  been  treated  with  a  blast  of  warm  air.  The  dan- 
gers in  its  use  lie  in  the  difficulty  in  preventing  pressure  upon  the 
pulp  cither  when  applied  or  in  mastication. 

Cotton  as  a  Retainer  of  arsenic  should  be  entirely  discontinued 
as  it  has  nothing  to  recommend  it  and  everything  to  condemn  it. 

Caution  in  the  Use  of  Arsenic  about  the  teeth  is  of  great  impor- 
tance and  when  used  it  must  be  sealed  in  the  dry  cavity  absolutely 
moisture  proof  and  particularly  when  any  of  the  cavity  outline  is 
sub-gingival  as  any  leakage  at  this  point  will  result  in  great  destruc- 
tion to  the  gums  and  alveolar  process.  Such  accidents  are  all  too 
frequent  and  the  injury  thus  done  is  never  fully  repaired. 

The  Length  of  Time  an  Arsenical  application  should  he  left  \n 
the  tooth  is  most  uncertain  and  there  seems  to  be  no  set  rule.  Neither 
the  condition  of  the  pulp  nor  the  amount  of  dentine  intervening  can 
be  taken  as  certain  in  judging  the  time.  However  it  is  most  com- 
mon practice  to  see  the  case  in  about  one  week's  time,  as  in  this 
time  a  majority  of  the  cases  will  have  become  devitalized  and  the 
natural  process  of  exfoliation  has  taken  place  between  the  dead  pulp 
and  the  living  tissues  at  the  apex  of  the  root  enabling  the  opera toi- 
to  remove  the  i)uli)  without  pain  or  hemorrhage. 

Primary  Soreness  of  the  Tooth  to  percussion  genei-ally  indicates 
the  death  of  the  pulp.  If  an  attempt  is  made  to  remove  the  pul]) 
too  soon  great  pain  will  result  as  the  pulp  is  yet  vital,  hence  it  is 
best  to  wait  until  the  pulp  has  been  fully  affected.  Again  during 
the  primajy  soreness  and  particularly  during  the  first  twenty-four 
hours  of  this  conrlition  the  patient  cannot  tolerate  the  instrumenta- 
tion necessary.  Such  cases  should  ])e  left  from  twenty-four  to 
forty-eight  hours  from  the  time  pericemental  soreness  develops,  hav- 
ing applied  to  the  gum  over  the  afflicted  toolli  aconiic  ;ind  iodine 
when  it  will   generally  permit  of  treatment. 

Secondary  Pericementitis  is  rbingei-o\is  to  the  sub-dental  tissues 


218.  OPERATIVE   DENTISTRY 

and  no  arsenical  application  should  be  allowed  to  remain  until  this 
second  attack  appears,  as  the  loss  of  the  tooth  is  not  beyond  the  pos- 
sibilities of  snch  neglect. 

The  Treatment  of  Arsenical  Poisoning  due  to  its  escape  from  the 
cavity  is  as  follows:  Eemove  everything  from  the  tooth  cavity. 
I'lood  the  cavity  and  destroyed  tissues  with  a  forceful  stream  of 
tepid  water  to  remove  all  traces  of  the  arsenic  not  yet  absorbed. 
With  a  sterile  spoon  excavator  dissect  and  curet  away  all  necrotic 
tissue  continuing  until  hemorrhage  is  produced.  Again  flood  the 
parts  with  warm  water.  Dry  with  a  cotton  ball  and  lightly  paint 
the  wound  with  aconite  and  iodine,  repeating  the  treatment  every 
other  day  until  a  healing  is  effected. 

When  Pulp  Returns  Partially  Devitalized  as  is  evidenced  by  sen- 
sation, particularly  in  the  apical  third  of  the  canal,  it  is  best  to  open 
the  pulp  chamber  and  amputate  with  a  sharp  spoon  excavator  only 
the  coronal  portion.  Wash  chamber  with  warm  water  and  dry  with 
warm  air.  Apply  absolute  alcohol  working  same  towards  the  apex 
by  the  side  of  the  pulp  as  far  as  possible  without  causing  pain,  fol- 
lowing this  with  thorough  desiccation  with  warm  air.  Then  seal  in 
a  dressing  of  phenol  and  dismiss  for  one  week  or  even  longer  and 
the  case  will  usually  return  with  devitalization  complete.  This  treat- 
ment is  particularly  indicated  in  young  teeth  where  the  apical  fora- 
men is  large. 

The  Removal  of  the  Pulp  following  arsenical  devitalization  is 
practically  the  same  as  that  following  anesthetization,  except  that  in 
the  latter  case  there  is  danger  of  going  beyond  the  apex,  while  with 
the  arsenic  devitalization  method,  the  greater  danger  is  in  not  ex- 
tirpating the  pulp  entirely  to  the  apex  through  mistaking  a  vital 
pulp  stump  within  the  canal  for  vital  tissue  beyond. 

Immediate  Canal  Filling  following  arsenical  devitalization  is 
quite  universally  practiced  and  is  generally  satisfactory.  However, 
too  large  a  per  cent  is  followed  by  mild  or  severe  pericementitis, 
which  might  be  averted  by  dressing  the  canals  with  a  mildly  anti- 
septic anodyne  of  a  stimiulating  nature  for  a  few  days  before  filling 
the  pulp  canals. 

All  Treatments  Above  Referred  To  in  this  chapter  should  be 
carried  out  with  the  rubber  dam  in  place  at  each  sitting.  (See  chap- 
ter on  ''The  Filling  of  Pulp  Canals.") 


CHAPTER  XXXVI. 
MANAGEMENT  OF  PUTRESCENT  PULP  CANALS. 

By  "Putrescent  Pulp  Canals"  is  meant  that  condition  in  these 
spaces  resultiiiu-  from  i)Utrefaction. 

By  "Putrefaction"  is  meant  that  serial,  progressive  decomposi- 
tion through  which  albuminous  substances  are  finally  resolved  into 
the  end-products,  hydrogen  sulphid  (HoS),  carbon  dioxide  (COo), 
ammonia  (NH,),  water  (HoO),  and  hydrogen  phosphid  (PH3).  A 
distinguishing  feature  of  the  process  is  the  evolution  of  malodorous 
gases. 

The  Presence  of  Bacteria  is  necessary  to  the  process  of  putrefac- 
tion and  all  such  cases  must  be  approached  with  this  fact  in  mind, 
and  antiseptic  measures  and  precautions  are  paramount  from  the 
beginning  of  the  case  to  its  termination,  that  the  pericementum  may 
not  be  involved  in  the  destructive  process. 

There  Are  Four  Classes  of  Putrescent  Pulp  Canals,  according  to 
the  manner  in  which  they  are  presented,  symptoms  present  and  the 
method  of  treatment. 

First.  Those  eases  where  the  canals  are  open  and  exposed  to 
the  fluids  of  the  mouth  known  as  "open  putrescence"  and  which  are 
generally  the  result  of  the  encroachment  of  caries. 

Second.  Those  cases  wherein  the  pulps  die  under  a  filling  or  a 
layer  of  affected  and  infected  dentine,  the  integrity  of  which  will 
not  permit  of  the  passage  of  fluids  or  gases.  This  is  known  as 
"closed  putrescence"  and  is  the  result  of  extrinsic  infection. 

Third.  Those  cases  wherein  the  crown  is  integral  and  the  bac- 
teria necessary  to  putrefaction  have  entered  the  pulp  tissue  either  be- 
fore or  after  its  death  by  way  of  the  apical  foramen,  conveyed  there 
by  the  circulation  of  the  blood.  This  class  of  cases,  from  the  ap- 
parent autopathy  is  termed  "autogenous  putrescence."  Such  cases 
are  most  likely  to  follow  suppurative  processes  in  close  proximity  to 
the  arteries  leading  to  the  pulp,  yet  cases  are  seen  where  no  such  con- 
ditions can  be  diagnosed,  primary  to  the  pulp  symptoms,  and  are 
generally  traumatic. 

Fourth.  Those  cases  wherein  the  destructive  processes  have  been 
coriimunicated  to  the  pericementum,  and  are  known  as  "complicated 
putrescence."  There  may  be  pericemental  inflammation  in  any  of 
its  stages  with  or  without  soreness  to  percussion.  The  apical  space 
may  harbor  pus  without  other  communication  than  the  putrescent 

219 


220  OPEKATIVE   DENTISTRY 

pulp  canal  or  there  may  be  an  abscess  with  a  sinus  passing  through 
the  alveolar  process  and  opening  through  the  gum. 

Treatment  in  General  may  be  stated  as  involving  the  removal  by 
mechanical  and  chemical  means  of  all  products  of  putrefaction,  thor- 
ough sterilization  of  all  surfaces  exposed,  conservation  of  vital  tis- 
sues beyond  the  apical  foramen  and  the  permanent  closure  of  the 
foramen  to  the  passage  of  fluids  and  gases. 

The  Symptoms  of  Open  Putrescence  (Class  One)  are  not  marked 
where  the  pulp  is  entirely  putrescent,  unless  there  are  pericemental 
complications,  when  the  case  would  come  under  the  heading  of  com- 
plicated putrescence.  "When  a  portion  of  the  pulp  is  yet  vital  it  is 
probable  that  the  pulp  is  undergoing  a  cellular  disintegration  through 
surface  ulceration.  This  is  usually  a  painless  process  and  is  re- 
sponsive only  to  the  encroachment  of  foreign  substances  which  lacer- 
ate its  tissues  or  produce  pressure  within  its  substance.  Such  cases 
call  for  sterilization  and  extirpation.  However,  with  simple  open 
putrescence  the  symptoms  are  largely  objective,  the  operator  dis- 
covering the  conditions  through  instrumentation,  and  the  noxious 
gases  encountered. 

Treatment  of  Open  Putrescence.  Excavate  the  cavity  to  com- 
plete exposure  of  the  pulp  chamber.  Flood  with  a  stream  of  water 
from  the  syringe.  Apply  the  rubber  dam  and  sterilize  all  teeth  and 
surfaces  exposed.  For  this  purpose  use  a  ten  per  cent  solution  of 
formaldehyde  to  which  has  been  added  a  small  amount  of  borax. 
Another  efficient  sterilizing  agent  is  bichloride  of  mercury,  in  the 
proportion  of  one  part  to  five-hundred  of  cinnamon  water.  Mechan- 
ically remove  the  contents  of  the  pulp  chamber  and  flood  the  open 
cavity  with  hydrogen  dioxide,  repeating  the  dioxogen  two  or  three 
times  or  until  active  effervescence  ceases.  Apply  absolute  alcohol 
and  evaporate  to  complete  dryness.  With  an  extra  fine  barbed  broach 
mechanically  clean  each  root  canal  with  hydrogen  dioxide.  Care 
should  be  taken  not  to  force  any  of  the  putrescent  matter  through 
the  foramen.  Remove  the  contents  of  the  canal,  portion  by  portion. 
The  canals  should  then  be  dried  with  alcohol  evaporation.  Follow 
this  with  a  fifty  per  cent  solution  of  sulphuric  acid  which  is  allowed 
to  remain  three  or  four  minutes  when  it  should  be  thoroughly  diluted 
with  water  and  the  canals  dried.  Apply  campho-phenique  and  desic- 
cate to  dryness.  For  the  final  dressing  flood  with  phenol,  pumping 
it  to  the  apex  of  said  canal  with  a  smooth  broach.  To  this  add  a 
paste  made  by  mixing  iodoform  with  phenol  sufficiently  stiff  to  be 
handled  to  the  cavity  on  a  large  spoon  excavator.  If  crystallization 
takes  place  add  a  drop  of  water.    Avoid  glycerine  or  alcohol.     By  a 


MANAGEMENT    OF    PUTRESCENT    PULP    CANALS  221 

pumping  motion  of  the  broach  the  paste  will  he  thinned  and  follow 
the  phenol  already  in  the  canal  to  the  apex. 

By  alternately  adding  the  paste  and  absorbing  the  excess  phenol 
the  canal  can  be  filled  with  a  comparatively  thick  paste.  Fill  the 
pulp  chamber  with  a  pellet  of  dry  cotton.  Seal  the  cavity  with  tem- 
porary stopping  or  cement,  preferably  for  a  week  or  ten  days,  when 
the  ease  will  almost  invariabh  return  ready  for  permanent  canal 
tilling.  If  a  shred  of  vital  pulp  is  encountered  in  the  apical  third 
it  will  have  been  devitalized  by  the  phenol  and  that  without  pain  or 
noticeable  soreness. 

The  Chief  Objection  to  This  Form  of  Treatment  is  the  obnoxious 
odor  of  the  iodoform.  The  deodorized  preparations,  however,  will 
not  accomplish  the  desired  results.  Care  should  be  taken  that  the 
iodoform  is  kept  moist  at  all  times  and  finally  deposited  in  the  foun- 
tain spittoon.  Each  teacher  has  a  different  treatment  for  putrescence 
and  the  student  is  advised  to  familiarize  himself  with  all.  However 
the  above  is  a  one-sitting,  successful  treatment  and  its  trial  is  ad- 
vised particularly  where  other  methods  have  resulted  in  pain  to  the 
patient  and  oft-repeated  visits  to  the  dental  chair. 

In  Cases  of  Long  Standing'  Putrescence,  which  are  generally  open 
cases,  the  dentine  is  thoroughly  saturated  with  poisonous  ptomaines, 
amido  acids  and  end  products.  These  must  be  gotten  rid  of  and 
the  most  expedient  method  is  to  chemically  change  these  irritating 
gases  and  poisonous  liquids  into  non-irritating  and  non-poisoning 
liquids  and  solids.  This  is  most  successfully  done  through  the  use 
of  formaldehyde.  Formaldehyde,  however,  is  very  irritating  to  vital 
tissues  and  should  not  be  Ijrought  into  contact  with  them.  There- 
fore its  use  is  contraindicated  in  cases  of  large  apical  foramen.  Also 
not  indicated  in  cases  where  a  portion  of  the  vital  pulp  remains,  as 
many  times  intense  pain  will  be  induced.  To  modify  the  irritating 
effects  there  may  be  added  to  a  ten  per  cent  solution  of  formalde- 
hyde an  equal  bulk  of  either  phenol,  creosote,  oi*  creosol,  the  latter 
being  preferable.  This  should  l)e  sealed  in  the  cavity  and  crown  ends 
of  the  canals  for  twenty-four  oi-  forty-eight  houi-s  before  thorough 
broaching  of  the  canals  is  attempted.  Following  the  removal  of  the 
above  treatment  the  canals  should  I'cceive  a  bath  first  of  water  and 
then  of  alcohol  to  carry  away  in  solution  the  compounds  resulting 
frr)iii  the  fbctiiica]  action  of  the  formaldehyde. 

Animal  Fats,  which  consist  of  carbon,  hydrogen  and  oxygen,  arc 
liable  to  be  jn-cscnt  in  abundance  in  recent  cases  of  putrescence  and 
should  be  removed  from  the  dentinal  walls  as  tliey  i-eadily  undergo 
fr-riiicnt alive  dccotii position. 


.  222  OPERATIVE    DENTISTRY 

Their  Removal  Is  Best  Accomplished  by  saponification  through 
the  action  of  sodium  dioxide.  This  should  be  applied  at  the  time  of 
broaching  the  canals,  using  a  platinum  broach.  Following  its  use 
the  canals  should  receive  a  water  bath. 

Symptoms  of  Closed  Putrescence  (Class  Two).  Closed  putres- 
cence without  complications  is  usually  of  short  duration  and  when 
they  are  presented  for  treatment  before  complication  there  generally 
remains  a  portion  of  the  pulp  in  the  apical  region  yet  vital. 

The  chief  pathognomonic  symptom  is  that  heat  produces  paroxysms 
of  pain  w^hile  cold  applications  bring  relief. 

The  Treatment  for  Closed  Putrescence  is  to  apply  the  rubber  dam 
and  with  a  small  drill  open  directly  to  the  pulp  chamber  when  tem- 
porary relief  will  be  immediate.  The  opening  should  then  be  en- 
larged and  the  necrotic  pulp  tissue  removed.  If  no  vital  pulp  tis- 
sue is  found  the  case  should  be  proceeded  with  as  before  outlined 
for  cases  of  open  putrescence.  When  a  vital  portion  of  the  pulp  re- 
mains nothing  will  be  more  palliative  than  the  phenol  and  iodoform 
paste  treatment  already  outlined.  This  paste  will  also  devitalize  the 
remaining  portion  of  the  pulp.  Pressure  anesthesia  is  certainly  not 
indicated  in  such  cases  from  the  liability  of  infecting  the  pericemen- 
tum. Neither  is  an  arsenical  application  permissible  within  a  pulp 
canal,  hence  the  phenol  treatment  is  the  best  practice. 

Autogenous  Putrescence  of  the  Pulp  (Class  Three)  are  occasion- 
ally met  with  and  may  be  of  long  standing  without  complications  of 
the  apical  tissues  and  only  discovered  when  the  dentine  of  the  crown 
is  found  to  be  non-vital.  Such  cases  are  generally  of  traumatic 
origin  primarily,  the  putrescent  condition  developing  long  after  the 
death  of  the  pulp  by  the  egress  through  the  apical  foramen  of 
facultative  anaerobic  bacteria.  Such  cases  are  dealt  with,  when 
treated,  as  any  case  of  closed  putrescence,  excepting  that  extra 
precaution  as  to  access  must  be  taken  as  the  admittance  of  the 
air  to  such  cases  seems  to  render  the  putrescent  matter  most  viru- 
lent and  the  dangers  of  complications  are  most  extreme.  Cases  pre- 
sented, of  recent  origin,  -which  may  be  classed  as  autogenous  are 
generally  complicated  when  they  come  to  the  dentist  as  the  com- 
plication is  the  cause  of  the  patient's  visit,  w'hen  they  would  be 
classed  as  a  case  of  closed  putrescence.  Their  cause  is  the  en- 
trance of  infection  through  the  circulation,  the  bacteria  having 
been  picked  up  in  pus  areas  not  far  distant  from  the  apical  fora- 
men. Strictly  speaking  there  are  no  autogenous  diseases  or  condi- 
tions, such  as  auto-infection  as  all  in  this  life  is  the  result  of  ex- 


MANAGEMENT    OF    PUTRESCENT   PULP    CANALS  223 

trinsic  causes  more  or  less  remote  from  the  body  but  the  classifica- 
tion of  autogenous  putrescence  of  the  pulp  is  given,  based  upon 
the  same  theories  and  principles  as  those  applied  in  general 
pathology,  wherein  the  iininediate  cause  is  not  at  all  apparent. 

The  Symptoms  of  Complicated  Putrescence  (Class  Four)  vary 
from  slight  soreness  to  percussion  to  the  symptoms  accompanying- 
most  violent  and  acute  inflammatory  processes  even  with  general 
febrile  disturbances.  Other  cases  will  present  themselves  with  an 
entire  absence  of  all  the  above  symptoms,  the  only  evidence  of 
pericemental  complications  being  detected  by  observation  or  in- 
strumentation. It  is  generally  true  that  the  acute  cases  show  the 
more  marked  symptoms,  and  the  extremes  of  easy  and  difficult 
management  are  encountered,  whereas  Avith  chronic  complications 
the  symptoms  are  not  so  marked  and  generally  yield  to  stereo- 
typed methods  of  treatment  except  where  great  destruction  of  tis- 
sue has  taken  place,  where  such  cases  shoukl  come  under  the  head 
of  surgery. 

The  Treatment  in  Complicated  Putrescence  is  as  varied  as  the 
symptoms  presented  and  the  conditions  found.  The  first  order  of 
procedure  is  the  removal  of  the  cause  which  includes  the  elimina- 
tion of  the  putrescent  conditions  Avithin  the  pulp  canal  under 
aseptic  precautions.  If  the  pericementum  is  only  inflamed  and  the 
presence  of  pus  is  not  probable,  the  treatment  is  the  same  as  that 
outlined  for  uncomplicated  putrescence,  adding  external  applica- 
tions to  the  gum  over  the  affected  tooth  to  stimulate  resolution. 
Painting  with  aconite  and  iodine  is  suggested. 

In  Acute  Complication  Avhere  pus  has  formed  and  upon  broach- 
ing is  freely  evacualed  dov/n  the  pulp  canal,  it  is  the  best  of  sur- 
gery to  alhiw  free  drainage  ])y  this  route  for  twenty-four  or  forty- 
eight  hours  before  attempting  further  treatment.  At  the  end  of 
this  time  the  most  active  symptoms  Avill  have  generally  subsided 
and  the  case  can  l)e  proceeded  witli.  However,  fhere  have  been 
some  cases  so  deeply  affected  beyond  the  apex  of  the  tooth  that  ex- 
ternal pointing  on  the  alveolar  wall  is  pi-obable  and  only  avoided 
by  immediate  extraction  of  the  tooth.  In  such  cases  the  salvage  of 
the  tooth  depends  upon  the  ability  of  the  patient  to  withstand  the 
pain  to  the  termination.  They  may  be  assisted  in  this  through  the 
general  administration  of  sedatives.  Locally  the  ai)])licati()ii  of  re- 
vulsives to  the  gum  will  hasten  the  external  jxiiiiling.  Evacuation 
ushers  in  the  stage  of  convalescence  and  the  treatment  of  the  pulp 
canals  may  be  proceeded  Avith. 


224  OPERATIVE    DENTISTRY 

In  Chronic  Complications  of  Putrescence  Avliere  the  drainage  is 
through  the  pulp  canal  only,  the  case  may  answer  to  the  treat- 
ment of  the  pulp  canal.  However  other  cases  will  demand  special 
treatment  for  the  sterilization  of  the  enclosed  pocket  beyond  the 
foramen.  The  greatest  danger  in  the  treatment  of  this  class  is  in 
suddenly  converting  them  into  acute  form.  This  can  generally  be 
avoided  by  attempting  the  treatment  of  the  sub-dental  conditions 
only  following  complete  and  absolute  sterilization  of  the  communi- 
cating canal.  That  there  is  a  communicating  canal  in  these  cases 
of  so-called  ''blind  abscesses"  is  self-evident  and  this  opening  per- 
mits of  treatment  without  the  use  of  pulp  canal  drills,  a  method 
"which  is  not  advised  and  a  practice  wholly  unwarranted,  result- 
ing, many  times,  in  rendering  the  case  beyond  the  possibilities  of 
cure. 

If  the  case  must  have  additional  drainage  it  is  a  case  of  surgi- 
cal procedure  and  the  point  of  attack  should  be  through  the  ex- 
ternal alveolar  wall,  a  method  sometimes  resorted  to  with  good  re- 
sults. 

Chronic  Alveolar  Abscess  With  Sinus,  generally  with  the  opening 
on  the  external  alveolar  wall,  is  a  complication  resulting  from  a 
closed  case  of  putrescence  of  long  standing  and  when  not  associated 
with  necrosis  or  denuded  root  is  not,  as  a  rule,  hard  to  manage. 

The  Treatment  of  Chronic  Alveolar  Abscess  is  to  thoroughly 
sterilize  the  pulp  canal,  then  the  fistulous  tract.  The  tract  should 
be  established  by  forcing  hamamelis  or  cassia  water  through  the 
pulp  canal  and  out  through  the  sinus.  Follow  this  with  phenol  or 
aconite  and  iodine  only  sufficient  to  cauterize  the  entire  surface  of 
the  tract  thus  destroying  the  fibrous  lining,  improperly  called  the 
"pyogenic  memhrane."  Then  proceed  as  with  any  other  case  of 
putrescence,  filling  the  pulp  canal  before  closure  of  the  sinus  has 
been  effected.  Some  advise  the  entire  treatment  and  canal  filling 
at  the  first  sitting,  but  it  is  probable  that  better  results  will  be  ob- 
tained if  case  is  allowed  a  week  or  ten  days  between  the  first 
treatment  and  the  canal  filling  for  complete  sterilization  of  the 
dentine  walls. 


CHAPTER  XXXVII. 
THE  FILLING  OF  PULP  CANALS. 

It  Is  Necessary  to  Fill  Pulp  Canals  following  the  removal  of  the 
pulp,  to  prevent  the  exit  of  bacteria  or  their  products  to  the  tis- 
sues beyond  the  foramen,  and  to  prevent  the  dissolution  of  the  en- 
compassing "walls  of  dentine. 

A  Pulp  Canal  Is  Ready  for,  and  should  receive  the  root  filling 
v.hen  the  canal  is  void  of  all  else  than  air  and  it  is  not  desired  to 
again  reach  the  pericemental  tissues  for  treatment.  To  render  a 
canal  void  of  all  else  than  air  is  by  no  means  universally  easy,  yet 
it  is  the  object  sought  and  the  conditions  are  not  ideal  until  this 
result  is  obtained.  This  involves  the  removal  of  all  pulp  tissue, 
moisture,  bacteria  and  their  products  as  well  as  all  medicines  and 
chemicals  used  in  the  process  of  treatment. 

The  Perfect  Pulp  Canal  Filling  is  one  which  permanently  occu- 
pies the  entire  space  of  the  pulp  canal  and  closes  the  apical  fora- 
men to  the  exit  or  entrance  of  all  substances,  particularly  gases 
and  fluids. 

The  Requirements  of  a  Material  for  Filling  a  Pulp  Canal  are 
that  it  be  non-soluble  in  the  fluids  of  the  body,  that  it  be  non-irri- 
tating to  soft  tissues,  permanent  as  to  bulk  and  consistency,  not 
subject  to  putrefaction  or  chemical  changes,  capable  of  easy  intro- 
duction, and  it  is  an  additional  virtue  if  it  can  be  again  removed 
i'l'oin  the  canal  after  months  or  even  years  of  occupancy. 

The  Objective  Point  in  Pulp  Canal  Filling  is  in  the  region  of  the 
foramen.  This  point  must  be  reached,  made  surgically  and  thera- 
peutically clean,  completely  vacated  and  then  permanently  sealed 
with  a  suitable  material. 

Small  Pulp  Canals  and  particularly  if  they  are  tortuous,  are  a 
hindrance  to  always  attaining  ideal  results  and  even,  in  rare  cases, 
Ihwai't  effort  to  save  teeth  thus  afflicted. 

The  Means  of  Cleansing  and  Vacating  small  and  toi-tuous  canals 
are  lioth  mechanical  and  chemical. 

It  Is  Best  Accomplished  mechanically  by  the  use  of  small,  flex- 
ible, bluiil-poiiilcd  1\\ist(*(l  reamers,  A\'hich  enlarge  the  canal  to  the 
extent  of  entrance  by  cutting  away  the  sides  to  increase  their  cal- 
iber until  broaches  of  other  forms  will  be  admitted.  This  process 
is  assi.sted  chemically  by  flooding  the  canal  with  a  fifty  per  cent 

22;'» 


226  OPERATIVE    DENTISTRY 

solution  of  sulphuric  acid,  as  this  will  dissolve  and  soften  the  den- 
tinal walls,  thus  facilitating  the  enlargement  of  the  canals. 

In  Cases  Where  the  Root  Is  Bent  on  Its  Long-  Axis  it  is  essential 
that  the  broach  should  be  rounded  and  blunt  of  point  that  it  may 
follow  the  canal  and  not  cut  its  side  wall  at  the  bend  of  the  canal, 
Avhich  will  produce  a  shoulder  and  hinder  further  progress.  This 
is  essential  with  the  finest  of  broaches  and  requires  preparation  on 
the  part  of  the  dentist  of  every  broach  used  in  this  class  of  work, 
as  all  broaches  that  come  from  the  factory  have  a  very  sharp  point 
entirely  unfitting  them  for  opening  crooked  pulp  canals.  This 
blunting  process  is  best  accomplished  by  holding  the  end  of  the 
broach  at  an  obtuse  angle  on  the  face  of  a  fine  cuttle  fish  disk  while 
revolving  in  a  dental  engine,  at  the  same  time  twisting  the  broach 
from  right  to  left. 

The  Carrying'  of  Cotton  into  a  Pulp  Canal  is  of  assistance  in  the 
drying  process  and  requires  the  special  preparation  of  a  broach  to 
facilitate  the  application. 

The  Cotton- Carrying"  Broach  is  prepared  by  taking  a  perfectly 
smooth  fine  hook  broach  and  by  grasping  Avith  a  pair  of  flat-nosed 
pliers,  say  the  sixty-fourth  part  of  an  inch  from  the  end,  rocking 
the  pliers  l-»ack  and  forth  until  the  end  is  broken  off.  This  results 
in  a  blunt  broken  surface  on  the  end  Avhich  engages  the  fibers  of 
the  cotton  twist  and  prevents  same  from  slipping  up  the  broach 
towards  the  handle,  as  it  is  introduced  into  the  canal,  alloAving  the 
cotton  to  be  carried  to  the  depth  that  the  caliber  of  the  canal  will 
permit. 

The  Cotton  Is  Applied  to  the  broach  by  taking  a  fcAV  fibers  be- 
tAveen  the  thumb  and  first  finger,  placing  around  the  broach, 
lAvisting  the  handle  of  the  broach  to  the  right,  and  at  the  same 
time  moA'ing  the  thumb  and  finger  to  roll  the  broach  in  the  same 
direction.  The  use  of  Red  Cross  absorbent  points  is  better 
practice. 

If  It  Is  Intended  to  Leave  the  Cotton  in  the  Canal  as  a  dressing, 
I'oll  upon  the  broach  tightly  at  the  point  only,  and  Avhen  introduced 
to  the  entire  depth  of  the  canal  tAvist  the  broach  to  the  left  part  of 
a  turn  and  use  a  tamping  motion,  and  the  cotton  Avill  be  disen- 
gaged and  packed  in  the  canal. 

If  It  Is  Intended  to  Remove  the  Cotton  With  the  Broach,  roll 
tightly  its  entire  length  and  Avhen  the  cotton  is  being  introduced, 
as  Avell  as  during  AvithdraAvah  tAvist  the  broach  to  the  right  con- 
tinuouslv,  as  this  Avill  cause  the  broach  to  maintain  a  tight  hold  on 


Tin:  KiLLi.N"(;  of  imjlp  canals  227 

the  cotton.  AVhen  all  has  been  removed  ^rasp  the  cotton  between 
the  finsrers,  twist  bi'oach  to  the  left  and  cotton  is  easily  disenfj^aj^ed. 

The  Most  Popular  Root  Filling  of  today  is  gutta-percha,  a  por- 
tion of  which  is  dissolved  in  dilorofoi'm  to  facilitate  its  introduc- 
tion. HoAvever  the  less  ainoiiiil  of  chloroform  or  any  othei-  fluid 
there  is  in  the  finally  completed  fillinrr,  the  better,  as  these  coiistil- 
uents  a  1-0  not  permanent. 

Methods  of  Use.  The  canal  must  he  cnlircly  vacant  except  the 
air  which  it  contains,  for  its  entire  length,  not  forgetting  that  this 
includes  the  removal  of  all   moisture  jiossible. 

The  First  Step  Is  to  Replace  This  Air  with  a  fluid  that  is  a  sol- 
vent for  the  gutta-percha  canal  filling.  A  very  popuhn-  substance 
foi-  this  purpose  is  the  oil  of  eucalyptol  as  this,  in  addition  to  being 
a  solvent  for  gutta-percha,  is  slightly  antiseptic  and,  being  an  oil, 
does  not  mix  with  any  blood  serum  or  moisture  that  has,  per- 
chance, escaped  the  operator's  notice  in  the  apical  end  of  fhe 
canal,  or  may  have  a  tendency  by  capillary  attraction  to  exude 
into  the  mouth  of  the  foramen,  floating  the  same  from  the  walls. 

The  Introduction  of  Chlora-Percha  is  accomplished  by  dipping 
a  small  broach  into  the  container  and  carrying  the  broach  thus 
loaded,  to  each  canal.  Carry  same  to  the  foramen  and  by  a  pump- 
ing motion  the  chlora-percha  is  mixed  with  the  eucalyptol,  and  no 
air  or  moisture  will  be  imprisf»ned  within  the  canal. 

The  Introduction  of  the  Gutta-Percha  Canal  Point  is  here  ac- 
complished by  grasping  the  large  end,  which  may  be  flattened 
with  the  cotton  pliers  or  attaching  same  to  the  warmed  end  of  a 
canal  plugger,  then  withdrawing  the  smooth  broach  which  has 
been  allowed  to  remain  part  way  up  the  canal  and  immediately 
entering  the  small  end  of  the  canal  point  aiid  shoving  entirely  to 
place  by  a  steady  gentle  pressure. 

The  Size  of  the  Canal  Point  should  be  great  enough  to  entirely 
fill  the  canal.  It  should  be  about  a  millimeter  longer  to  permit  of 
slight  tamping  at  the  mouth  of  the  canal.  The  size  may  have  been 
previously  ascertained  by  measurement  and  trial,  which  is  good 
practice  for  a  beginner.  An  experienced  operator  will,  in  most 
instancos,  be  able  to  judge  as  to  size  without  measurement. 

Slight  Flinching  on  the  part  of  the  patient  or  the  sense  of  full- 
i;e.ss  is  quite  a  trustworthy  guide  as  to  having  reached  the  apical 
end  of  canal  in  recent  eases  of  devitalization,  but  such  symi)toms 
should  not  be  sought  in  devitalized  teeth  of  long  standing,  partic- 
ularly if  there  has  been  a  loss  of  any  of  the  tissue  in  the  apical 
HI)ac(!.     However,   in   these  cases  as  with   all   (jthers,   care   should  be 


228  OPERATIVE   DENTISTRY  ■* 

taken  that  perfect  and  complete  filling  of  the  apical  foramen  has  j 

been  accomplished,  which  is  ideal.     Yet  to  fill  slightly  beyond  the  j 

canal  by  a  fraction  of  a  millimeter  is  a  less  error  than  to  not  en-  | 

tirely  fill  the   canal.     The   opening   of  the   canal  should  now  be  i 

tamped  solid,  which  process  is  aided  by  warming  the  protruding  ^ 

end  of  the  canal  point.  i 

Cleanse  Pulp  Chamber  of  all  traces  of  gutta-percha  and  case  is  j 

ready  for  final  operation.  ■ 

TTie  practice  of  filling  pulp  cliamhers  with  gutta-percTia  in  any 

form  is  condemned  as  it  is  in  no  way  suitable  for  the  seat  of  a  fill-  ' 

ing.    Cement,  amalgam  or  tin  is  preferable.  J 


CHAPTER  XXXVIII. 
MANAGEMENT  OF  CHILDREN'S  TEETH. 

The  management  of  children's  teeth  presents  tAvo  difficulties  ad- 
ditional to  the  management  of  the  teeth  of  adults. 

The  First  Difficulty  and  many  times  the  most  important  is  the 
management  of  the  child.  Children  are  very  susceptible  to  exter- 
nal influence  and  even  when  quite  young  believe  all  they  hear. 
The  conversation  of  the  older  ones  about  the  home  pertaining  to 
the  "horrors"  of  the  dental  office,  has  many  times  so  poisoned  the 
mind  of  the  child  that  it  prejudges  the  dentist  and  his  efforts  to 
the  extent  of  preferring  any  other  punishment  rather  than  meet 
the  dentist,  even  for  an  examination. 

The  First  Visit  of  a  Child  should  be  made  one,  wherein  there  is 
an  entire  absence  of  pain,  oi"  even  inconvenience  on  the  part  of  the 
child. 

Such  visits  should  be  repeated  till  absolute  confidence  has  been 
secured.  After  this  has  been  thoroughly  established,  the  children 
of  a  clientele  will  prove  as  easily  managed  as  the  adults,  and  in 
after  years  are  the  most  tenacious  patrons,  seldom  changing  their 
dentist  through  life. 

The  Second  Difficulty  with  the  management  of  deciduous  teeth 
is  the  comparatively  sliort  life  of  the  most  careful  operations.  The 
teeth  are  themselves  but  temporary.  All  about  them  is  a  panorama 
of  change  and  we  can  hope  at  best  for  onh^  temporary  results. 
Parents  should  be  given  to  understand  this  feature  of  the  services 
and  not  be  led  to  misjudge  the  skill  of  an  operator  by  the  results 
of  operations  on  the  teeth  of  children. 

Early  Attention  is  imperative  and  the  keynote  to  success.  All 
small  eiiaiiiel  defects  should  be  sought  out  and  fillings  made  as 
soon  as  such  are  found  to  exist.  It  is  hopeless  to  attempt  the  sal- 
vage of  deciduous  teeth  after  the  pulps  have  boconio  involved  and 
subdental  «lis()i'(lors  have  boon  established. 

Oral  Hygiene  With  Children  should  be  established  early.  The 
parents  should  receive  thorough  instructions  as  to  the  use  of  the 
toothbrush,  with  or  without  a  dentifrice,  as  the  child  ])i'of(M's,  and 
fi  daily  attention  established  by  the  time  1lic  lull  loiiiporai y  don- 
tnro  is  ornpted. 

Frequent  Visits  to  the  Dentist  arc  osscntijil;  oven  more  than 
with  adnlts,  as  the  (k'strnctive  i)roc(!ss  rnns  a    rapid   cunisc   \\licn 

229 


230  OPERATIVE   DENTISTRY 

once  established,  a  few  weeks'  neglect  often  resulting  in  irrepara- 
ble injury.  These  visits  should  be  established  at  regular  and  fre- 
quent intervals,  as  the  most  unhygienic  conditions  may  result  from 
only  a  few  days'  neglect  and  upon  early  detection  and  eradication 
depends  the  success  of  interference. 

Length  of  Time  at  Each  Sitting  should  not  exceed  thirty  min- 
utes for  a  child  under  twelve  years  of  age  and  should  not  exceed 
one  hour  until  after  eighteen  years  of  age.  Great  care  should  be 
exercised  in  causing  the  child  any  considerable  amount  of  pain. 
Better  that  the  filling  consist  of  temporary  stopping  to  last  but  a 
few  days  than  to  cause  lasting  memories  of  dental  pains  inflicted 
by  the  dentist. 

The  Filling  Materials  to  Be  Used  are  limited  to  those  of  speedy 
manipulation,  and  those  requiring  a  minimum  of  convenience 
form.  This  will  place  in  the  list,  amalgam,  tin,  gutta-percha  and 
cements. 

Cavity  Preparation  should  be  limited  to  the  removal  of  the  ma- 
jor portion  of  decay,  sterilization  and  securing  the  cleavage  of  the 
enamel  in  cavity  outline  by  the  use  of  the  chisel.  All  else  should 
be  avoided. 

Extension  for  Prevention,  Extension  for  Resistance,  Flat  Seats 
for  Fillings,  Line  Angles  and  Point  Angles  and  all  else  in  cavity 
Ijreparation  so  carefully  applied  to  filling  the  teeth  of  adults 
should  be  ignored  when  dealing  with  deciduous  teeth.  If  decay 
has  not  left  the  cavity  naturally  retentive,  cement  should  be  re- 
sorted to  instead  of  cutting. 

Cavities  of  Class  One.  Pit  and  fissure  should  be  filled  with 
amalgam  or  tin  under  as  dry  conditions  as  can  be  secured  without 
the  rubber  dam.  The  use  of  the  rubber  dam  should  be  restricted 
to  the  six  anterior  superior  teeth  and  when  used  should  be  very 
loosely  ligatured. 

Cavities  of  Class  Two.  Proximal  cavities  in  molars  should  be 
filled  with  amalgam.  When  the  retentive  form  is  not  good  in  the 
cavity  without  much  cutting,  the  amalgam  should  be  laid  in  soft 
cement. 

When  Two  Cavities  Exist  in  molar  proximal  space  which  are 
not  retentive  it  is  good  practice  to  fill  the  two  cavities  as  one, 
counting  on  refilling  the  cavity  in  the  second  molar  if  the  first 
molar  is  lost  early,  or  perchance  Avhen  this  has  failed,  which  it  will 
sooner  or  later,  the  cavities  will  return  with  independent  retentive 
form. 


MANAGEMENT    OF    CHILDREN'S    TEETH  231 

Cavities  of  Class  Three  should  be  tilled  ^vith  ceiuent  with  rubber 
clam  in  position.  If  decay  has  progressed  till  angle  is  lost  or  par- 
tially so,  do  not  build  to  contour  but  fill  as  a  Class  Three. 

Classes  Four,  Five  and  Six  may  be  ignored. 

Treatment  of  Exposed  Pulps  in  Deciduous  Teeth.  Pulp  devital- 
ization with  deciduous  teeth  should  never  be  attempted.  Pressure 
anesthesia  will  not  prove  successful.  Arsenic  should  never  be  ap- 
plied to  deciduous  teeth.  The  risk  is  too  great  and  is  condennied 
in  every  case.  If  the  pulp  is  exposed  and  aching,  clean  out  the 
debris,  flood  Avith  warm  Avater,  dry  and  phenolize.  Apply  a  pledget 
of  cotton  saturated  with  oil  of  cloves  for  twenty-four  hours. 
When  case  returns,  dry  and  again  phenolize  and  apply  a  paste  of 
phenolized  iodoform  over  which  place  a  filling. 

If  the  pulp  has  begun  to  suppurate,  the  necrosed  tissue  should 
be  cut  away  and  the  space  filled  with  a  paste  made  of  oil  of  cloves 
and  the  oxide  of  zinc  powder,  over  Avhich  is  placed  a  filling  of  tem- 
porary stopping.  The  pulp  will  usually  die  under  this  without 
further  pain. 

When  the  case  returns,  which  should  be  in  about  two  or  th]-ee 
weeks,  the  canals  should  be  cleansed  and  filled  with  a  paste  made 
from  campho-phenique  and  iodoform  and  cavity  filled  with  a 
plastic  filling. 

Treatment  of  Abscessed  Deciduous  Teeth.  Such  teeth  should  be 
allowed  or  assisted  to  point  externally,  as  they  Avill  generally  have 
progressed  almost  to  the  stage  of  pointing  before  the  dentist  is 
\isited. 

As  soon  as  the  active  stage  has  subsided,  the  case  should  be 
given  the  above  treatment  for  putrescence  and  filled.  If  abscess 
persists,  as  Avill  occasionally  be  the  case  in  spite  of  all  methods,  a 
small  hole  should  be  bored  in  the  buccal  surface  just  sub-gingivally 
to  the  pulp  chaiii])er,  leaving  the  filling  in  place. 

Inter-Proximal  Grinding  is  of  service  Avhen  tilling  is  out  of  the 
question.  This  is  practiced  much  after  the  same  method  it  was 
used  in  primitive  days  Avith  the  permanent  teeth. 

The  proximal  surfaces  are  cut  away  so  that  they  ai-e  non-reten- 
tive to  food  particles  and  the  sides  of  the  remaining  surfaces  thor- 
oughly exposed  to  the  excursions  of  food  in  mastication.  With 
antci'ior  teeth  the  contact  i)oiiit  is  thereby  moved  to  near  the 
gingival  line.  With  posterior  teeth  the  contact  point  is  removed 
as  far  to  the  buccal  as  possible  by  widening  the  lingual  embrasui-e 
at  the  expense  of  both  proximating  teeth.  This  method  is  un- 
sightly in  the  ;intei-ior  teeth  and  not   altogethci-  without   its  objec- 


232  OPERATIVE    DENTISTRY 

tions  when  used  on  posterior  teeth,  but  it  is  nevertheless  good  prac- 
tice in  many  cases  as  it  materially  retards  the  process  of  decay. 

The  Management  of  Permanent  Teeth  in  Childhood  constitutes 
one  of  the  greatest  trials  of  dental  practice  and  is  at  the  same  time 
of  the  utmost  importance.  These  teeth  are  erupted  at  a  time  of 
life  vv^hen  the  oral  conditions  are  the  most  favorable  to  decay. 
Again  these  teeth  are  expected  to  give  their  user  the  longest  period 
of  service  of  any  of  the  entire  set  of  permanent  teeth. 

It  Requires  Extra  Vigilance  on  the  part  of  the  dentist  to  prevent 
irreparable  injury  to  the  first  permanent  molars,  as  the  parents  are 
not  usually  aware  that  permanent  teeth  are  present  at  this  age 
and  do  not  assist  the  dentist  in  detecting  incipient  decays.  More 
is  expected  and  required  of  the  first  permanent  molar  than  any 
other  tooth.  It  must  stand  the  onslaught  of  the  most  unhygienic 
conditions. 

It  must  give  its  possessor  longer  years  of  service  and  that  in  a 
position  in  the  mouth  most  often  subjected  to  the  stress  of  masti- 
cation. Slight  faults  in  enamel  should  be  sought  out  early  and 
filled  with  amalgam  to  be  changed  for  gold  in  more  mature  years. 
When  badly  broken  down  they  should  be  restored  to  full  contour 
v/ith  amalgam  and  croAvned  only  when  the  second  permanent  mo- 
lar is  fully  in  position.  If  gold  is  used,  it  should  be  in  the  form  of 
the  inlay  under  about  fourteen  years  of  age  as  the  tooth  should 
not  receive  severe  and  prolonged  condensing  force  till  certain  of 
full  development,  which  is  from  ten  to  fourteen  years  with  the 
first  permanent  molar. 

Treating  First  Permanent  Molars.  In  treating  and  filling  the 
root  canals  of  these  teeth  before  fully  developed,  the  apical 
foramen  will  many  times  be  found  quite  large.  In  some  cases  the 
circulation  is  so  great  that  devitalization  is  most  difficult.  In  un- 
certain cases  it  is  well  to  use  a  medicated  root  canal  filling  that  is 
easy  of  removal  and  instruct  patient  to  return  in  a  few  months  or 
perhaps  a  year  for  final  filling. 

A  Good  Root  Filling  for  Such  Cases  is  phenolized  iodoform  for 
the  canals,  topped  with  gutta-percha  base  plate  for  the  pulp  cham- 
ber and  covered  with  amalgam.  When  the  case-  returns  it  will 
generally  be  possible  to  determine  the  length  of  the  root  and  size 
of  the  foramen  when  a  correct  root  filling  of  chlora-percha  will  be 
possible.  In  applying  arsenic  for  devitalization  in  teeth  that  have 
not  fully  developed  as  may  be  expected  from  their  age,  great  care 
should  he  exercised,  as  there  is  great  danger  of  apical  arsenical 
poisoning  which  nearly  always  causes  the  speedy  loss  of  the  tooth. 


CHAPTER  XXXIX. 
EXTRACTION  OF  PERMANENT   TEETH 

General  Consideration.  Under  normal  conditions  tooth  extrac- 
tion is  not  a  difficult  operation.  However,  there  is  no  oral  surgeon 
even  of  experience  who  meets  with  universal  success.  There  are 
abnormal  conditions  which  render  unsuccessful  any  attempts  at 
removal  by  ordinary  means;  but  if  the  patient  is  placed  under  an 
anesthetic  there  are  instruments  manufactured  and  competent  and 
able  surgeons  to  handle  them,  that  can  remove  the  tooth  entirely, 
and  if  need  be  the  entire  maxillie  with  it.  Yet  there  is  a  limit  to 
all  operations. 

There  is  a  time  to  stop.  All  oral  surgeons  have  had  the  same  ex- 
perience, finding  cases  where  the  unavoidable  injury  to  the  tissues 
in  removing  the  tooth  would  do  more  harm  than  allowing  a  small 
part  of  the  tooth  to  remain.  To  the  laity,  however,  the  skillful  ex- 
traction of  a  tooth  seems  ' '  quite  a  trick. ' '  For  instance,  the  black- 
smith or  a  man  of  great  strength,  who  has  not  made  a  careful  study 
of  the  teeth  and  their  environment,  may  attempt  to  extract  the 
tooth  and  fail.  One  who  has  made  the  subject  a  study,  although 
possessed  of  far  less  strength,  removes  the  same  tooth  skillfully 
and  seemingly  without  the  exertion  of  much  muscular  effort.  Un- 
less the  force  is  properly  and  scientifically  applied,  it  accomplishes 
nothing  but  injury.  If  the  force  is  applied  in  a  proper  direction, 
Avith  proper  movements,  the  dislocation  of  a  tooth  is  quite  an  easy 
matter.  The  old  saying  that  there  is  no  rule  without  an  exception, 
and  that  the  exception  proves  the  rule,  will  apply  to  the  rules  for 
extraction;  for  there  is  pi-obably  as  much  difference  in  the  forma- 
tion of  teeth  and  adjacent  structure  as  in  the  facial  expression  of 
different  persons.  Tlierefore  it  is  difficult  to  formulate  any  rules 
which  we  can  follow  literally  in  all  cases.  Still  the  extraction  of 
teeth  is  best  acconiplishod  by  the  application  of  scientific  principles. 

These  princij)les  ])r()|)('i'ly  applied  will  give  better  results  than 
extracting  the  teeth  merely  to  get  them  out.  For  tliis  reason  we 
must  study  that  which  we  wish  to  accomi)lish  and  how  l)est  to  ac- 
complish it,  by  considering  the  various  shapes  of  that  part  of  the 
teeth  which  cause  their  retention  in  the  jaw;  also  the  structures, 
sti-fiitrt})  anrl  ])osi1ion  of  Ihose  tissues  wliicli  hold  Ihe  tee1h  in  place. 

Principal  Retention.     The  constricted  ixmHoii   of  a   lootli   at  its 

23.3 


234  OPERATIVE   DENTISTRY 

neck  serves  to  retain  the  tooth  firmlj''  in  the  alveolar  process,  and 
constitutes  its  principal  retention,  by  the  process  grasping  the 
tooth  at  this  point,  assisted  by  natural  adhesion  of  the  tissues. 

Opening  Mouth  of  Alveolus.  The  alveolar  process  is  just  a  lit- 
tle thicker  or  heavier  at  the  neck  of  the  tooth  than  just  below. 
The  gingival  part  of  the  alveolus,  the  tooth's  socket,  is  called  the 
mouth  of  the  alveolus.  This  mouth  once  opened,  which  can  be  ac- 
complished by  slight  fracture  at  this  point,  the  removal  of  a  normal 
tooth  is  made  easy. 

How  Can  This  Best  Be  Accomplished?  By  application  of  force 
in  the  line  of  least  resistance.  This  varies  in  different  teeth,  owing 
to  the  difference  in  anatomical  structure,  the  number  of  roots  and 
direction  of  eruption. 

Three  Forces  Are  Applied  in  the  Extraction  of  a  Tooth:  Trac- 
tion, Eotation  and  Pressure. 

Traction  is  a  pulling  force ;  rotation  is  a  motion,  given  the  hand 
in  using  a  screw  driver,  but  moving  the  hand  first  in  one  direction 
then  in  another.  Pressure  is  the  force  we  would  apply  to  a  tooth 
in  endeavoring  to  push  it  in  or  out  of  the  mouth  at  an  angle  to  its 
long  axis. 

Position  and  Movements.  If  the  patient  is  of  mature  years  and 
as  is  often  the  case  possessed  of  as  much  or  more  strength  than  the 
dental  surgeon,  it  is  very  essential  that  Ave  consider  position  and 
movements  and  that  we  have  so  calculated  these  matters  that  the 
patient  is  at  all  times  fully  under  the  control  of  the  operator.  It 
is  not  well  to  give  the  patient  to  understand  that  we  think  this 
particular  tooth  is  a  very  difficult  one  to  extract,  or  that  we  are  in 
the  least  timid  about  performing  the  operation. 

Securing  Patient's  Confidence.  After  it  has  been  decided  to 
extract  the  tooth,  the  more  precise  and  deliberate  the  operator's 
actions,  the  more  confidence  the  patient  will  have,  hence  a  firm  but 
gentle  hand  instills  into  the  patient's  mind  confidence  in  the  oper- 
ator's ability.  In  giving  the  positions  of  the  patient  and  operator, 
it  is  assumed  that  the  latter  is  right  handed.  If  such  is  not  the 
case,  the  positions  would  be  reversed. 

Position  of  Patient's  Head.  The  patient's  head  should  be  in- 
clined backward.  It  should  be  firmly  fixed  and  absolutely  under 
the  control  of  the  operator.  This  can  be  accomplished  in  different 
ways  in  the  absence  of  a  dental  chair  with  its  head  rest  and  other 
conveniences,  in  which  case  the  operator  may  be  compelled  to  re- 
sort to  very  primitive  means. 


EXTRACTIOX    OF    PERMANENT    TEETH 


235 


With  All  Superior  Teeth  the  operator  should  stand  back  of  the 
patient  and  a  little  to  the  right,  placing  the  crown  of  the  head 
against  the  chest  of  the  operator,  putting  the  left  hand  around  to 
the  left  of  patient's  head  with  the  index  finger  holding  the  lip  away 


I'ig.   109. — An  improper  position  with  the  operator  doing  his  work  at  arm's  length. 

from  the  alveolar  process  and  at  the  same  time  lying  against  the 
process,  to  detect  at  once  any  extensive  injury  which  miglit  lesult 
from  a  fracture.  The  middle  or  second  finger  should  be  placed  back 
of  the  forceps  when  the  tooth  it  on  the  left  side;  or  against  The 
palatine  process  when   the  tooth   is  on  the   right  side.     Then  bv 


236 


OPERATIVE    DENTISTRY 


Fig.  110. — Types  of  superior  central  incisors.  The  first  row  sliows  tlie  labia],  the  second  row 
the  lingual,  the  third  row  the  mesial,  and  the  fourth  row  the  distal  surface.  (From  Winter's 
Elxodontia.) 


EXTRACTION    OF    PERMANENT    TEETH 


237 


I'lK-  1)1  Tyjiij.',  of  sujjcrior  lateral  intisois.  The  lirst  row  shows  llie  labial,  the  secoid  row 
the  lirigtial,  the  third  row  the  mesial,  and  the  fourth  row  the  distal  surface.  (P'roin  Winter's 
Kxodontia.; 


238 


OPERATIVE   DENTISTRY 


pressing  the  patient's  head  firmly  against  the  head  rest,  or  against 
the  operator's  chest,  if  using  a  low  chair  or  stool,  it  is  entirely 
from  under  the  control  of  the  patient,  when  inclined  in  a  backward 
position. 


Fig.    112. — Position   for   extracting  superior   incisors. 

The  Position  in  Extracting  the  Lower  Teeth  is  nearly  the  same, 
except  that  the  relative  position  of  patient  should  be  lower.  The 
general  position  for  all  inferior  bicuspids  and  molars  is  the  same 
as  for  the  superior.  In  extracting  inferior  incisors  and  cuspids 
stand  directly  behind  the  patient,  and  use  a  straight  or  bayonet- 


EXTRACTION    OF    PERMANENT    TEETH 


239 


I'ig.  113. — -Types  of  inferior  central  and  lateral  incisors.  The  first  row  shows  the  labial,  the 
scconJ  row  the  lingual,  the  third  row  the  mesial,  and  the  fourth  row  the  distal  surface.  (From 
Winter's   Exodontia.) 


240 


OPERATIVE   DENTISTRY 


shaped  forceps,  such  as  are  used  in  the  extraction,  of  superior  in- 
cisors. The  patient's  head  should  be  the  height  of  the  operator's 
waist  line,  he  standing  directly  back  of  patient. 

Position  of  Hands.     The  index  finger  should  press    down    the 


Fig.   114. — Position  for  extracting  lower  incisors. 


lower  lip  and  inspect  the  alveolar  process.  The  thumb  should  be 
placed  on  the  lingual  surface  of  the  process  and  the  three  remain- 
ing fingers  should  grasp  the  chin  firmly,  that  the  lower  jaw  may  be 
fully  under  control. 

Operating  at  Arm's  Length.     In  no  case  leave  your  patient  or 


EXTRACTION    OF    PERMANENT    TEETH 


241 


i  .«.    11... — 'lyi'c.-)    1,1    7,Li|iLiH)i    cuspids.      The    liist    row    shows    tliu    laljiii 
lingual,  the  third   row  the  mesial,  and  the  fourth   row  the  distal  surface, 
dontia.) 


,    the    second    row    the 
(From  Winter's  Exo- 


242 


OPERATIVE   DENTISTRY 


step  in  front  of  him,  using  the  hand  and  your  forceps  at  arm's 
length,  for  with  the  head  at  liberty  a  sudden  twitch  or  jerk  on  the 
part  of  patient  would  either  destroy  or  misguide  the  force  applied 
and  either  thwart  the  effort  to  remove  the  tooth  or,  perhaps,  by 


Fig.  116. — Position  for  extracting  right  superior  cuspids. 


increasing  the  pressure  in  the  wrong  direction  cause  permanent 
injury.  (See  Fig.  109.)  Just  as  an  operator  is  extracting  the 
tooth,  he  is  often  troubled  by  the  patient  grasping  the  arm  which 
is  using  the  forceps.    This  is  a  serious  matter,  especially  when  ex- 


EXTRACTION    OF    PERMANENT    TEETH 


243 


traeting  a  lower  tooth,  as  the  line  of  force,  which  the   operator 

■wishes  to  exert  is  opposite  to  that  in  which  the  patient  can  exert 

great  force  thus  resulting  in  diminishing  the  power  of  the  former. 

Overcoming'  Resistance  of  Patient.    At  this  point  the  operator  is 


h"ig.    117.- — Position   for   extracting   left   su|)erior   cuspids. 


justified  in  a  sharp  reprimand,  even  hordcting  ujx)!)  crossness,  per- 
liaps  getting  the  patient  to  desist  for  a  moment,  when  the  opera- 
tion may  be  completed.  The  only  precaution  for  guarding  against 
such  a  turn  of  affairs  is  perhaps  a  suggestion  tlial  tlic  i)a1i('iit  hold 


244 


OPERATIVE   DENTISTRY 


the  hands  of  a  friend  or  grasp  the  arm  or  seat  of  the  chair,  instruct- 
ing him  to  give  a  vigorous  pull  just  as  you  start  to  extract  the 
tooth.  This  may  assist  him  to  endure  the  pain  which  is  sometimes 
unavoidable  Avhen  local  or  general  anesthetics  are  contraindicated. 


Fig.  118. — Mesial  and  distal  application  of  forceps  to  a  superior  right  cuspid  when  both 
adjacent  teeth  have  been  extracted  in  advance  of  the  cuspid.  The  forceps  illustrated  is  the 
author's  No.  4. 


In  Superior,  Central  and  Lateral  Incisors  traction  or  force  is  ap- 
plied parallel  to  its  long  axis.  Next  rotation.  Why?  Because  this 
is  a  single-rooted  tooth  and  the  root  is  slightly  rounded.  Also, 
should  any  of  the  adhering  portions  of  the  alveolar  process  be  in 
danger  of  removal,  the  rotary  motion  will  loosen  that  portion  from 
the  tooth. 


EXTRACTION    0¥   PERMANENT   TEETH  245 

For  example,  if  upon  the  removal  of  a  nail  from  a  board,  part 
of  the  board  should  adhere,  the  twisting  of  the  nail  would  remove 
from  it  the  adhering  wood  by  hiringing  it  in  contact  Avith  the  great- 
er body  of  the  board.  Next  comes  pressure,  outward,  or  labial,  he- 
cause  this  is  in  the  line  of  least  resistance  as  the  process  is  much 
thinner  on  the  labial  than  on  the  lingual  aspect. 

Do  not  alternate  the  motion  between  labial  and  lingual  pressure, 
as  any  pressure  lingually  accomplishes  nothing  but  increased  pain, 
for  before  the  tooth  can  be  removed  the  mouth  of  the  alveolus  must 
be  opened  and  this  can  only  be  effected  by  labial  pressure. 

All  change  of  force  should  be  of  a  rotarj-  nature,  with  a  slight 
labial  pressure,  and  sufficient  traction  to  remove  the  tooth  upon 
the  slightest  fracture,  or  giving  of  the  process  at  the  mouth  of  the 
alveolus. 

In  Inferior,  Central,  and  Lateral  Incisors  traction  should  be  in 
a  line  ijarallel  with  the  long  axis  oi  the  tooth.  No  rotation  is  neces- 
sary because  these  teeth  have  flat  roots  with  their  greatest  trans- 
verse diameter,  labio-lingual.  Any  twi.sting  or  attempts  at  rotat- 
ing these  four  teeth  will  only  endanger  their  slender  roots.  Pres- 
sure is  slightly  labial,  because  this  is  in  the  line  of  least  resistance, 
the  process  being  thinner  on  the  labial  aspect. 

Superior  Cuspids.  A  considerable  amount  of  force  is  required 
to  remove  this  tooth,  as  it  is  the  longest  tooth  in  the  human  mouth. 
It  is  generally  most  firmly  seated  and  as  a  rule  requires  more 
force  for  its  removal  than  any  other.  Slight  rotation  is  required, 
especial]}-  when  the  first  bicuspid  and  lateral  incisor  are  in  posi- 
tion. The  root  of  this  tooth  is  not  quite  so  nearly  round  as  that 
of  the  central  incisors,  but  rotation  should  be  applied  to  prevent 
a  fracture  of  the  adhering  process  of  the  lateral  .surface.  This 
rotation  tends  to  peel  or  scale  off  any  adhering  process  by  bring- 
ing it  in  contact  with  the  firmer  portion  not  disturbed. 

Pres.sure  must  be  steadily  labial,  as  this  is  in  the  line  of  the  least 
resistance.  By  "steadily  outward,"  we  do  not  mean  to  gra.sp  the 
tooth,  and  draw  it  out  at  right  angles  with  the  long  axis  of  the 
tooth;  but  that  in  addition  to  the  great  amount  of  traction  neces- 
sary and  the  slight  rotation  there  should  be  a  certain  amount  of 
labial  pressure  upon  the  process. 

There  is  one  case  where  this  rule  for  the  extraction  of  the  su- 
perior cuspid  may  be  ignored.  That  is  when  the  first  bicuspid  and 
lateral  incisor  have  just  been  extracted.  In  this  case  instead  of 
grasping  the  cu.spid  labio-lingually,  place  the  beaks  of  the  forceps 


246 


OPERATIVE   DENTISTRY 


t^.'^itJ^^'^IP''®  of  inferior  cuspids.     The  first  row  shows  the  labial,  the  second  row  the  lingual 
the  third  row  the  mesial,  and  the  fourth  row  the  distal  surface.      (From  Winter's  Exodontia  ) 


EXTRACTION    OF   PERMANENT    TEETH 


247 


a  short  distance  up  into  the  cavities  of  the  freshly  extracted  teeth, 
thus  grasping  the  tooth  mesio-distally.  Then  give  the  tooth  great 
traction  and  also  rotation  in  one  direction.  This  rotation  should 
be  so  applied  that  the  labial  portion  of  the  cuspid  would  be  moved 


Fig.    120. — Position   for  extracting  inferior  cuspids. 


towards  the  median  line.  The  reason  the  motion  should  l)e  applied 
only  in  this  direction  can  be  found  in  llic  fact  that  frequently  the 
roots  of  cuspid  teeth  turn  or  bend  backward,  as  they  advance  up 
in  the  y)rocess.     Using  traction  and  rotation  in  this  one  direction 


248 


OPERATIVE   DENTISTRY 


■=,irf^.^;  nf  fTTf  F  °S  ^"P^"°i"^  first  and  second  bicuspids.  First  row— first  four  teeth,  buccal 
fi"^n^,  °/.!  f^  bicuspids;  second  four  teeth,  buccal  surface  of  second  bicuspids.  Second  row— 
bir,^«;nH,  ^Ih  Z^^'^/'^^^f''^  °/  ^^"*  bicuspids;  second  four  teeth,  lingual  surface  of  second 
bicuspids.  Third  row— first  four  teeth,  mesial  surface  of  first  bicuspids;  second  four  teeth  mesial 
Wteeth  '%Z^  bicuspids.  Fourth  row-first  four  teeth,  distal  su^fac^  of  first  bicuspids;'  second 
tour  teeth,   distal  surface   of  second  bicuspids.      (From  Winter's   Fxodontia.) 


EXTRACTION    OF   PERMANENT    TEETH 


249 


the  principle  is  applied  which  removes  a  corkscrew  from  a  cork, 
right  or  left  thread. 

Inferior  Cuspids.     Traction  with  slight  rotation.     Labial  pres- 
sure.    The  rnles  for  the  extraction  of  inferior  cuspids  are  quite 


Fig.    122. — Position   for  extracting  right   superior  bicuspids. 


similar  to  those  for  the  superior  cuspids,  adding  only  that  owing 
to  the  curve  sometimes  found  in  its  single  root,  it  is  well  to  direct 
the  lino  of  traction    force  a  little  backward. 

Superior    Bicuspids.      Principally    tractions,    parallel    with    the 


250 


OPERATIVE   DENTISTRY 


long  axis  of  the  tooth.  Owing  to  the  small  size  of  the  root  in  both 
cases  and  the  first  bicuspid  frequently  having  a  double  root,  other 
forces  must  be  sparingly  used  in  the  removal  of  this  tooth.  Minute 
rotation,  could  only  be  used  in  second  bicuspid,  this  being  a  single- 


Fig.  123. — Position  for  extracting  left  superior  bicuspids. 


rooted  tooth.  The  first  bicuspid  is  generally  possessed  of  two 
roots.  When  not  sufficiently  bifurcated  to  be  classed  as  two  dis- 
tinct roots,  they  are  so  united  as  to  form  a  very  flat  root  with  the 
greatest  diameter  bucco-lingually. 


EXTRACTION    OF   PERMANENT    TEETH 


251 


Fig.  124.— Types  of  inferior  first  and  second  bicuspids.  First  row — first  five  teeth,  buccal  sur- 
face of  first  bicuspids;  second  five  teeth,  buccal  surface  of  second  bicuspids.  Second  row — first  five 
teeth,  lingual  surface  of  first  bicuspids;  second  five  teeth,  lingual  surface  of  second  bicuspids. 
Third  row— first  five  teeth,  mesial  surface  of  first  bicuspids;  second  five  teeth,  mesial  surface 
of  second  bicuspids.  Fourth  row — first  five  teeth,  distal  surface  of  first  bicuspids;  second  five 
teeth,  distal  surface  of  second  bicusjiids.     (From  Winter's  ICxodontia.) 


252 


OPERATIVE   DENTISTRY 


Pressure,  which  is  outward  as  this  is  in  the  line  of  least  resist- 
ance owing  to  the  thinness  of  process  on  buccal  aspect,  must  be 
sparingly  used;  not  so  much  because  you  would  endanger  the 
process  by  great  force  in  this  direction,  for  it  is  considerably  thick- 


Fig.   125. — Position  for  extracting   right  inferior  bicuspids. 

er  over  the  bicuspid  than  over  the  cuspid  roots,  but  because  there 
is  danger  of  breaking  the  root  just  below  the  mouth  of  the  alveolus, 
or  close  to  where  the  roots  begin  their  bifurcation.  With  the  sec- 
ond superior  bicuspid  the  pressure  outward  may  be  greater,  bear- 


EXTRACTION    OF   PERMANENT    TEETH 


253 


ing  ill  mind  that  the  roots  of  these  teeth  are  disproportionally  long 
compared  with  their  circumference  at  the  neck. 

Inferior  Bicuspids.    Principally  traction.    In  applying  this  force 
bear  in  mind  that  the  line  of  the  greatest  length  of  these  teeth  is 


Fig.  126. — Position  for  extracting  left  inferior  bicuspids. 


normally  inclined  backward  instead  of  being  in  all  cases  at  a  right 
angle  to  the  plane  of  occlusion.  Therefore,  the  traction  must  be 
applied  in  a  direction  which  would  move  the  tooth,  if  it  suddenly 
came  loose,  towards  the  first  molar  or  back  of  Avhere  it  normally 


254 


OPERATIVE   DENTISTRY 


Fig.  127. — Types  of  superior  first  and  second  molars.  The  first  row  shows  the  buccal,  the 
second  row  the  lingual,  the  third  row  the  mesial,  and  the  fourth  row  the  distal  surface.  (From 
Winters  Exodontia.) 


EXTRACTION    OF   PERMANENT    TEETH 


255 


occludes.  Minute  rotation  is  necessary  for  the  reason  that  these 
are  also  slender-rooted  teeth  and  quite  frequently  somewhat 
curved.  As  a  rule  these  teeth  are  possessed  of  but  one  root.  The 
pressure  should  be  minutely  buccal,  for  this  is  in  the  line  of  least 


Fig.   128. — Position  for  extracting  first  and  second  right  superior  molars. 


resistance.  Care  should  be  taken  not  to  injure  the  upper  teeth 
when  inferior  bicuspids  and  first  molars  leave  their  sockets  sud- 
denly, as  they  sometimes  do.  Injury  to  the  other  teeth  through 
striking  them  with  the  forceps  is  more  likely  to  occur  in  extracting 


256 


OPERATIVE   DENTISTRY 


bicuspids,  as  the  force  of  traction  should  be  applied  in  a  direction  ] 

which  would  bring  them  in  contact  with  the  upper  teeth.  I 

Superior  First  and  Second  Molars.    These  teeth  are  grouped  to-  ] 

gether,  as  in  the  case  of  the  bicuspids,  on  account  of  similarity  in  i 


Fig.    129. — Position  for  extracting  first  and  second  left  superior   molars. 


form,  position  and  parts  surrounding  them.     Traction  should  be  1 
applied  in  the  direction  of  a  line  drawn  from  the  central  pit  of  this  ; 
tooth  to  the  apex  of  the  lingual  root.     No  rotation  should  be  ap- 
plied.    Any  motion  in  the  way  of  rotation  would  not  loosen  the  \ 


T:XT[Mr'(i(),V    ()]■    I'l  K\!  \  \l   VT    'llC'lJf 


l-iK.  1.!').  Tyi,«--  of  inf. -nor  !;•-»  .-in.!  -.:"..•")  n,',l;jr-^.  I'ir^'  r'<w  lirht  i'y'jr  H-clh,  )/a':'.;jl  '^Mf- 
face  of  lirst  molars;  TMrtoruJ  four  teeth,  buccal  surface  of  second  molars.  Second  row — first  four 
teeth,  lin((ual  surface  of  first  molars;  second  four  teeth,  lingual  surface  of  second  molars.  Third 
row — first  four  teeth,  mesial  surface  of  first  molars;  second  four  teeth,  mesial  surface  of  second 
molars.  Fourth  row — first  four  teeth,  distal  surface  of  first  molars;  second  four  teeth,  distal  sur- 
face of  second  molars.      (From   Winter's   Kxodontia.^ 


258 


OPERATIVE    DENTISTRY 


tooth,  as  one  root  would  brace  the  other.  It  is  therefore  advan- 
tageous to  apply  the  force  in  the  line  of  the  greatest  length  of  one 
of  these  roots,  the  lingual. 

Pressure  should  be  applied  steadily  buccally  and  not  released 
liiitil  the  mouth  of  the  alveolus  is  opened.     The  process  over  the 


Fig.    131. — Position  for  extracting  first  and  second   right  inferior  molars. 


lingual  root,  which  is  the  palatine  process  of  the  superior  maxillaB, 
is  quite  thick  and  heavy  and  seldom  gives  to  any  extent,  but  the 
two  buccal  roots  are  no  great  distance  from  the  soft  tissues  and  bv 


EXTRACTION    OF   PERMANENT    TEETH 


259 


this  steady  buccal  pressure  this  process  gives  and  the  tooth  is  al- 
loAved  exit.  Care  should  be  taken  not  to  make  this  pressure  too 
strong  or  apply  it  too  suddenly,  as  the  two  roots  in  such  close 
proximity  may  act  as  a  lever  and  loosen  a  considerable  portion  of 
the  buccal  plate. 


Fig.    132. — Position   for  extracting  first  and   second   left    inferior   molars. 


Inferior  First  and  Second  Molars.  Traction  is  necessary,  the 
Jorcc  of  wliicli  slunild  he  apj>lie(l  not  only  upvvai'd  but  backward, 
rememberinf?  that  the  apices  of  the  two  roots  are  nol  directly  un- 


260 


OPERATIVE   DENTISTRY 


Fig.  133. — Types  of  superior  third  molars.  The  first  row  shows  the  buccal,  the  second  row 
the  lingual,  the  third  row  the  mesial,  and  the  fourth  row  the  distal  surface.  (From  Winter's  Exo- 
dontia.) 


EXTRACTION    OF   PERMANENT   TEETH 


261 


I''iK.    134. — Types  of  al)norni;il    siiiierior    iliii 
rooted    teeth,   the    Ihirrl    row   shows   ticlh    with    root> 


Till-    lust    anil    second    rows   show    four- 
fuse*],    the    fourth    row   shows   teeth 


.  ...^.    ,    ....     .,,...,    ,.,„    .-,■■. ,vv7.    iiuiii    Willi    loois    iiiai    are    lused,    me    lourtn    row   snows   feetli 

hayini?  crowns  with  a  smRle  cone  and  only  one  root,  and  the  liflh  row  shows  teeth  having  roots  in 
which  there  is  great  variation  in   form.      (I'roiii    Winter's   J;xodonlia.; 


262 


OPERATIVE   DENTISTRY 


der  the  crown  but  posterior  to  it,  giving  the  root  a  curve  backward. 
A  common  error  is  made  when  the  force  of  traction  is  applied  at  a 
right  angle  to  the  plane  of  occlusion.  There  should  be  no  rotation. 
I'or  as  these  are  double-rooted  teeth  rotation  accomplishes  nothing 
except  to  increase  the  pain  by  alternately  increasing  and  releasing 
the  pressure  upon  the  highly  vascular  and  sensitive  peridental 
membrane.  Pressure  should  be  directly  buccal.  Although  it  may 
seem  t'o  the  operator  that  the  process  is  thinner  upon  the  lingual 
aspect  of  the  inferior  maxillffi,  this  is  generally  not  the  case.  Yet, 
as  with  all  lower  teeth,  a  malocclusion  or  an  irregularity  may  make 
the  process  thicker  on  the  buccal  surface. 

Superior  Third  Molars.  Rotation  is  applied  in  but  one  direction, 
one  that  would  roll  the  top  of  the  hand  towards  the  median  line. 
Pressure  should  be  buccal  and  at  the  same  time  distal.     Being  the 


Fig.  ISS.^One  of  the  many  abnormal  conditions  found  when  extracting  upper  second  and 
third  molars.  In  this  case  the  first  molar  was  the  only  one  which  had  erupted.  The  patient 
was  about  forty  years  of  age.  A  very  severe  abscess  appeared  beneath  the  tissues  overlying 
the  second  and  third  molars.  An  incision  revealed  the  condition.  The  photograph  shows  the 
result  of  extracting,  all  three  coming  out  attached. 


last  tooth  in  the  mouth  and  seated  at  the  angle  of  the  jaw,  it  is  not 
very  firmly  supported  by  the  process,  which  in  some  cases  is  almost 
entirely  wanting  on  the  posterior  buccal  corner. 

Inferior  Third  Molars.  Traction  should  not  be  only  upward, 
but  backward,  which  can  be  accomplished  after  grasping  the  tooth 
with  the  beaks  of  the  forceps,  and  allowing  the  handle  to  lie  across 
and  near  the  anterior,  inferior  teeth.  As  the  traction  is  applied  the 
handles  are  raised  and  have  an  amount  of  spring  which  will  tilt  the 
crown  backwards  in  proportion  to  the  distance  the  anterior  teeth  are 
separated  by  the  opening  of  the  mouth.  Here  we  have  the  only 
tooth  in  which  there  is  an  almost  universal  exception  to  the  direction 
in  which  the  pressure  should  be  applied  to  be  in  the  line  of  the 
least  resistance.  In  the  case  of  the  third  inferior  molar,  it  is  to  the 
lingual.     The  coronoid  process  of  the  inferior  maxillee  comes  down 


EXTRACTION    OF    PERMANENT    TEETH 


263 


endino:  in  the  external  oblique  line  which  is  an  eminence  and  ma- 
terially thickens  the  jawbone  just  buccal  to  the  third  molars. 

It  must  also  be  remembered  that  there  is  little  of  the  alveolar 
process  formed  around  the  third  molar,  seldom  more  than  that  por- 


Fig.   136. — Position   for  extracting  right  upper  thinl   molars. 


tion  which  buihls  in  a  round  tho  neck  to  insure  its  i-etentioii.  Thci'e- 
forc  when  th(!  tooth  is  broken  off  it  at  once  becomes  a  very  difficult 
task  to  remove  the  i"cmainiii<f  portion,  o\viii<!,-  to  the  strcnfj;t]i  and 
widtli  of  tlic  biMic  at  Ibis  point. 

Care  Should  Be  Taken  Not  to  Employ  Great  Pressure  Lingually 


264 


OPERATIVE    DENTISTRY 


as  the  anatomical  structure  at  this  point  favors  fracture  which  most 
frequently  extends  down  and  back  to  include  the  inferior  dental 
foramen  connected  with  the  mylohyoid  groove. 


Fig.  137. — Position  for  extracting  upper  left  third  molars.  Note  the  hand  grasp  on  the 
forceps.  This  grasp  can  also  be  used,  sometimes,  on  the  first  and  second  molars.  The  grasi> 
is  a  powerful  one  as  the  bones  and  muscles  of  the  arm  and  body  are  in  a  position  to  exert  a 
great  amount  of  force  while  giving  the  tooth  buccal  pressure  and  rotation  with  the  top  of  the 
forceps  moving  toward  the  median  line  in  the  rotary  motion  and  the  handles  of  the  forceps, 
are  pushed  out  and  back.  While  this  may  look  awkward  in  the  photograph  many  of  my 
students  who  have  tried  it  have  been  very  much  pleased  with  the  results. 


Injury  in  this  way  at  this  particular  point  may  be  far-reaching- 
in  its  effect,  as  fractures  are  most  likely  to  follow  weakened  portions; 


EXTRACTION    OF    PERMAXEXT    TEETH 


265 


Fig.    138. — Types  of  inferior  third  molars, 
the  lingual,  the  third  row  the  mesial,  and  the  fourth   row  the  distal  surface 


incomplete  and  malformed  molar  roots. 


The   first   row  shows  the  buccal,  the  second   row 
The  fifth  row  shows 
(From  Winter's  Exodontia.) 


266 


OPERATIVE   DENTISTRY 


Fig.    139. — Elevator   beaked   forceps   for   extracting   third   molars. 


Fig.    140. — Position   for   extracting   right    inferior   third  molars. 


EXTRACTION    OF   PERMANENT    TEETH 


267 


of  the  bone,  and  in  this  case  they  overlie  the  inferior  dental  nerve 
and  vessels. 

Hemorrhage  Following  Extraction.  Excessive  hemori'hatje  fre- 
quently follows  tooth  extraction,  and  is  more  frequently  met  with  in 
cases  after  extractino^  first  or  second  lower  molars. 


Fig.   141.  —  Position  for  extracting  left  inferior  third  molars. 

In  Mild  Cases  a  tamijon  of  cotton  salui-aled  willi  liydroj^cii  di- 
oxide or  adrenalin  chloride  crowded  well  to  the  bottom  of  the  alveolus 
from  wliif'li  tlif  licmorrhaf^e  is  cominj?  will  usually  be  sufficient. 

In  Severe  Cases  a  tampon  made  of  the  sci-apings  ol"  oak-tanned 


268  OPERATIVE'  DENTISTRY 

sole  leather  will  prove  effective.  T*he  scrapings  are  made  by  the  den- 
tist from  a  piece  of  sole  leather  by  scraping  shreds  from  the  edge. 
These  should  be  previously  prepared  and  ready  for  an  emergency. 
They  should  be  placed  in  a  large-mouthed  bottle  and  sterilized  by 
dry  heat  and  securely  corked. 

Method  of  Applying".  When  case  pi-esents,  there  should  be  three 
pellets  made,  small,  medium  and  large  about  the  size  of  the  al- 
veolus. These  should  be  introduced  quickly  one  after  the  other  and 
pressed  to  position  and  held  there  for  some  minutes  with  the  ball 
of  the  finger. 

The  leather  scrapings  will  swell  and  effectually  plug  the  alveolus. 
Also  the  tannin  in  the  leather  liberates  the  fibrinogen  and  an  im- 
pei-vious  clot  is  formed.  Within  twenty-four  hours  the  last  applied 
pellet  of  scrapings  will  have  been  raised  out  of  the  socket  and  the 
next  two  will  soon  follow. 

This  is  recommended  as  a  method  that  has  never  failed  in  a  long 
list  of  desperate  cases  but  should  not  be  resorted  to  except  as  an  ex- 
treme measure  as  great  soreness  frequently  follows  the  treatment 
due  to  the  interference  with  the  circulation  for  some  considerable 
distance  about  the  bleeding  alveolus. 

Hypodermic  Injections  of  Adrenalin  Chloride  for  hemorrhage 
following  extraction  is  good  practice.  Load  the  syringe  part  full 
with  Ringer's  solution  to  which  has  been  added  five  drops  of  ad- 
renalin chloride.  Introduce  the  needle,  which  should  be  long  and 
large,  into  the  apical  space  and  inject  a  few  drops.  Repeat  two  or 
three  times  if  necessary. 

Capillary  Hemorrhage.  If  the  hemorrhage  is  capillary,  inject 
into  the  tissues  from  which  the  blood  is  coming. 


CHAPTER  XL. 
EXTRACTION  OF  TEMPORARY  TEETH. 

The  extraction  of  temporary  teeth  at  the  proper  time  and  under 
normal  conditions  is  not  a  difficult  operation,  owing  to  the  amount 
of  phj^siological  resorption  of  both  alveolar  process  and  roots  of  the 
teeth. 

The  Most  Important  Thing  Connected  With  Their  Extraction  is 

an  accurate  knowledge  of  the  order  in  which  nature  proposes  to  re- 
place them  with  the  permanent  set. 

Results  From  a  Disregard  of  This  Order.  The  premature  or 
tardy  extraction  of  temporary  teeth  has  more  to  do  with  irregular 
and  unsightly  permanent  teeth  than  any  other  one  cause.  There- 
fore it  is  w^ell  to  make  a  careful  study  of  the  order  in  wdiich  the  tem- 
porary set  is  replaced. 

Time  of  Eruption  of  the  First  Permanent  Molar.  The  first  molar 
teeth  make  their  appearance  at  between  five  and  six  years  of  age. 

They  are  generally  supposed  by  the  laity  to  be  deciduous  and  are 
frequently  allowed  to  decay  beyond  remedy  before  the  mistake  is 
discovered.  They  are  then  extracted  without  much  thought,  either 
through  necessity  or  from  being  mistaken  for  temporary  teeth  by 
the  physician  on  account  of  the  youth  of  the  patient.  The  parents 
are  wonderfully  surprised  to  find  such  enormous  i-oots  on  Avhat  they 
believe  to  be  a  temporary  tooth. 

Duty  of  Dentist  in  This  Matter.  The  practitioner  of  dentistry 
has  a  very  important  duty  to  perform  in  insisting  upon  the  reten- 
tion of  this  tooth;  for  through  its  loss  a  decided  derangement  of  the 
permanent  set  results  and  lack  of  proper  development  of  the  jaw  is 
Olicoiii';if;('(l. 

First  Permanent  Tooth  to  Erupt.  Fig.  142  is  a  side  view  of 
child's  jaw  at  about  the  sixth  year.  No.  1  in  the  top  row  is  the 
fii'st  molar,  aiid  is  a  part  of  the  permanent  set,  the  second  and  third 
molai-s  coming  in  after  the  temporary  set  has  been  entirely  replaced 
by  i)crmanent  teeth. 

Reasons  for  a  Permanent  Tooth  at  This  Time.  Nature  in  giving 
us  tiiis  pci-mauc'iit  tooth  at  tliis  pjii-ticuhir  time  and  located  at  this 
particular  place,  seems  to  desire  to  put  in  a  permanent  fixture  as 
a  dividing  line  in  the  jaw  between  the  teeth  which  are  lo  be  replaced, 
an«1  lliosc  which  arc  not.  as  shown  by  lijie  A- A. 

Evil  Effects  of  Early  Extraction.     //  /;,//  /'roper  F.xirarlion  and 

269 


270 


OPERATIVE   DENTISTRY 


Coacliing  Into  Place  of  the  various  teeth  in  their  proper  order  the 
position  of  this  line  A-A,  which  bisects  the  jaw  just  at  the  mesial 
of  the  first  permanent  molar,  is  not  allowed  to  move  anteriorly,  there 
is  left  just  the  proper  space  which  the  permanent  teeth  will  occupy- 
when  they  replace  the  temporary  set,  provided  the  jaw  development 
is  not  interfered  with,  but  if  by  the  premature  extraction  of  the  sec- 
ond temporary  molar,  this  first  permanent  molar  is  allowed  to  tip 
forward,  thereby  moving  line  A-A  anteriorly,  we  have  encroached 
just  that  much  upon  the  space  required  by  the  permanent  teeth. 

The  Irregularity  Resulting  From  Such  a  Mistake  will  probably  be 
shown  in  the  cuspid  as  this  is  the  last  of  the  temporary  set  to  be 


3-3-6-4  -5 


i-3-!^-— 4— 5 


Fig.  142. — Represents  the  complete  set  of  deciduous  teeth  with  the  first  permanent  molar 
added.  Lower  row  of  figures  represents  the  order  the  deciduou  steeth  generally  erutp. 
Upper   row   of   figures   represents   the    order   of   the    replacement   by    the    permanent   set. 


replaced.  (See  Fig.  143.)  Again,  if  the  first  permanent  molar  is 
extracted  before  the  temporary  teeth  have  been  replaced,  nature 
seems  to  realize  that  further  development  of  the  jaw  on  this  side  is 
not  necessary,  and  the  jaw- — be  it  lower  or  upper — will  generally  lack 
in  length  to  correspond  with  its  antagonist,  the  width  of  the  tooth 
extracted.  This  may  not  be  noticed  in  the  exhibition  of  faulty  oc- 
clusion or  irregularities  but  a  careful  study  of  the  features  will 
show  lack  of  artistic  contour. 

Let  us  here  consider  the  order  in  which  the  temporary  teeth  are 
replaced  by  the  permanent  set.  By  reference  to  Fig.  142,  you  will 
see  that  the  order  differs  somewhat. 


EXTRACTION    OF    TEMPORARY    TEETH 


271 


The  lower  figures  represent  the  order  of  eruption  of  the  temporary 
set.  The  upper  figures  represent  the  order  of  the  replacement  by 
the  permanent  set  including  this  first  permanent  molar.  Nature  has 
wise  reasons  for  this  change  in  the  order. 

The  Inferior  Teeth  Generally  Precede  the  Superior  in  the  an- 
terior part  of  the  mouth  by  a  few  w^eeks  and  in  the  posterior  part 
by  a  few  months  with  the  exception  of  the  third  molars.  The  inferior 
third  molars  sometimes  precede  the  superiors  by  years.  It  must  also 
be  borne  in  mind  that  the  variance  in  length  of  time  and  age  of  erup- 
tion is  shorter  in  the  case  of  females  than  of  males. 

Difference  in  Time  as  to  Sex.  Some  females  erupt  their  third 
molars  as  young  as  the  sixteenth  year,  some  males  do  not  erupt  them 
as  late  as  the  twenty-seventh  year.  They  may  be  in  part  or  entirely 
wanting  in  either  male  or  female  during  life.     Thev  are  sometimes 


Fig.  143. — Irregularity  resulting  from  premature  extraction  of  the  first  deciduous  molar. 

so  far  retarded  that  they  do  not  erupt  until  after  the  extraction  of 
the  first  and  second  molars  late  in  life.  This  sometimes  gives  rise  to 
an  idea  in  the  patient's  mind  that  he  has  at  least  part  of  a  third  set 
of  teeth. 

Compare  Orders  of  Eruption.  A  careful  consideration  of  the 
two  tables  will  show  that  in  the  temporary  set  the  cuspid  teeth  erupt 
before  the  temporary  molars,  while  these  are  replaced  by  the  per- 
manent teeth  in  a  different  order.  The  first  temporary  molar  is  re- 
placed by  the  fii-st  Incuspid.  Then  the  second  temporary  molar  is 
replaced  by  the  second  bicuspid  and  next  we  have  the  cuspid  tooth 
comirii^  into  ])]nco,  forming  Ibe  keystone  of  the  arch. 

The  Reason  for  Nature's  Change  of  This  Order.  At  five  years 
we  find  the  full  (•onii)l(;nient  of  teinpoi-aiy  teeth  in  i)lace,  only  twenty 
in  number.  Then  nature  j)Uts  in  this  dividing  line  by  putting  into 
place  one  ])f'rnianent  tooth,  tho  first  permanent  molar,  before  she 


272  .  OPERATIVE   DENTISTRY 

makes  any  attempt  at  interfering  with  the  temporary  arch  already 
established. 

AVhen  this  tooth  is  fully  in  place  nature  begins  her  work  of  re- 
placement. First  come  the  centrals,  then  the  laterals,  and  if  Ave 
were  to  follow  the  order  in  which  these  same  temporary  teeth 
were  erupted  we  would  next  have  the  cuspid,  but  not  so,  we  have 
the  first  temporary  molar  lost  and  replaced  by  the  first  bicuspid, 
and  as  this  temporary  molar  is  lost,  the  first  bicuspid  has  a  space 
to  occupy  between  two  teeth,  which  should  be  in  position  to  guide 
and  assist  it  to  proper  place,  leaving  the  second  temporary  molar 
in  position  to  hold  the  first  permanent  molar  in  its  correct  posi- 
tion. Then  nature  replaces  the  second  temporary  molar  with  the 
second  bicuspid.  Note  that  these  two  temporary  molars  are  wider 
than  the  permanent  bicuspids  taking  their  place,  but  the  cuspid 
of  the  permanent  set  is  Avider  than  the  temporary  cuspid. 

Loss  of  Temporary  Cuspid.  As  soon  as  the  temporary  molars 
have  been  replaced  by  the  bicuspids,  the  temporary  cuspids  should 
be  lost  and  replaced  by  the  permanent  cuspids,  which  as  stated 
before,  forms  the  keystone  of  the  arch,  and  being  a  little  wider 
wedges  the  two  bicuspids  quickly  back  into  position  against  the 
first  permanent  molar.  Coming  into  position  just  in  this  order 
and  at  this  time  it  is  easily  seen  how  the  first  permanent  molar  is 
kept  in  its  proper  place.  At  this  time  the  question  may  arise  as  to 
how  the  permanent  centrals  and  laterals  find  sufficient  room,  be- 
ing so  much  larger  than  their  predecessors.  This  is  compensated 
for  by  the  development  of  the  maxillte  at  this  age.  Some  authors 
advance  the  idea  that  the  difference  in  the  space  occupied  by  these 
four  teeth  was  compensated  for  by  the  permanent  bicuspids  being 
smaller  than  the  temporary  molars.  We  cannot  agree  with  this. 
For  when  the  four  incisor  teeth  are  erupted  in  position  in  almost 
every  instance  the  temporary  cuspid  retains  its  former  and  original 
place. 

Having  completed  the  changing  of  the  temporary  teeth  nature 
will  add  teeth  to  the  posterior  part  of  the  jaw  without  any  danger 
of  subsequent  irregularities. 

Evils  Resulting  From  Disregarding  the  Order  in  Which  the 
Temporary  Teeth  Are  Replaced  by  the  Permanent  in  Their  Extrac- 
tion. For  instance,  if,  as  we  are  frequently  requested  by  our 
patrons,  we  extract  lateral  incisors  before  the  central  incisors  have 
attained  nearly  their  proper  height  in  the  process  of  eruption,  either 
one  of  the  two  evils  may  result. 


EXTRACTION    OF   TEMPORARY   TEETH  273 

The  central  incisors  in  the  inferior  maxilla  stand  on  either  side 
of  the  symphysis,  or  where  the  two  segments  of  the  jawbone  unite. 
In  the  superior  maxilla  the  central  incisors  stand  on  either  side  of 
the  median  line  in  the  intermaxillary  bones.  If  the  temporary 
laterals  are  extracted  before  the  centrals  are  fully  erupted,  should 
the  jaw  continue  proper  development,  the  central  incisors  will  stand 
apart  as  they  do  not  have  the  lateral  incisors  to  hold  them  toward 
the  median  line.  Thus  when  the  laterals  attempt  to  come  into  place, 
their  space  has  been  encroached  upon  and  they  may  fail  to  crowd 
the  centrals  over  to  place. 

HoAvever  in  most  cases  the  bones  do  not  continue  proper  develop- 
ment and  the  space  between  the  two  temporary  cuspids  occupied 
by  the  four  temporary  incisors,  is  not  sufficiently  increased  to  ac- 
commodate the  permanent  incisors;  hence  the  crowded  condition 
frequently  met  with. 

Therefore  no  lateral  incisors  should  be  extracted  until  the  cen- 
tral incisors  are  quite  in  position.  If  the  central  incisors  do  not 
seem  to  have  sufficient  room,  instruct  the  patient  to  put  pressure 
with  the  tongue  or  fingers  in  the  labial  direction  which  will  put 
them  into  proper  position;  but  for  no  reason  whatever  should  the 
laterals  be  extracted  before  the  centrals  have  attained  their  proper 
height  in  the  line  of  occlusion. 

Next  we  lose  the  lateral  incisors.  As  this  tooth  erupts  after  the 
temporary  lateral  has  been  extracted,  it  very  frequently  loosens  the 
temporary  cuspid,  which  by  this  time  has  had  its  root  quite  freely 
resorbed.  Patients  then  request  that  the  cuspid  be  extracted  as 
the  lateral  has  not  sufficient  room.  Very  frequently  it  will  look 
as  though  this  was  necessary.  However  if  we  extract  the  cuspid 
at  this  point  rest  assured  that  there  will  not  be  room  enough  for 
the  permanent  cuspid,  Avhen  it  wishes  admittance  to  the  arch.  We 
should  insist  upon  the  retention  of  the  cuspids  and  as  the  lateral 
crowds  for  room,  development  all  through  the  jaw  and  especially  at 
the  median  line  will  take  place. 

In  the  superior  jaw  the  intermaxillary  bones  materially  develop 
at  this  age,  and  as  the  temporary  cuspid  is  not  lost  until  between 
the  eleventh  and  thirteenth  year  the  development  is  ample.  So 
the  incisor  teeth  (the  two  centrals  and  two  laterals),  have  allotted 
to  them  the  space  between  the  temporary  cuspids,  as  well  as  that 
which  is  made  by  the  growth  of  the  jaw  between  the  time  of  their 
eruption  and  the  loss  of  the  cuspid  teeth. 

Therefore  the  lateral,  which  did  not  seem  to  have  space  enough 
when  it  erupted  will  have  ample  space  in  five  years  as  it  is  that 


274  OPERATIVE   DENTISTRY 

long  before  any  teeth  in  its  immediate  vicinity  are  disturbed.  Na- 
ture then  skips  this  cuspid  tooth  which  is  to  hold  the  incisors  in 
place,  and  the  first  temporary  molar  is  replaced  by  the  bicuspid 
which  has  ample  room  and  needs  little  attention  beyond  the  re- 
moval of  its  predecessor  at  the  proper  time.  Just  at  this  point  the 
second  temporary  molar  may  become  decayed  or  lost  and  patients 
will  insist  upon  its  extraction ;  but  if  by  any  means  the  patient  can 
be  made  comparatively  comfortable  it  should  not  be  extracted  as 
its  removal  allows  the  first  permanent  molar  to  move  forward 
caused  by  the  growing  and  developing  second  permanent  molar  at 
this  age.  When  the  first  bicuspid  is  fully  erupted  to  the  line  of 
mastication,  we  are  justified  in  removing  the  second  temporary 
molar  to  give  place  to  its  successor.  During  the  eruption  of  the 
first  bicuspid,  the  cuspid  will  very  frequently  become  loose  and  pos- 
sibly hard  to  retain,  and  the  patient  will  again  insist  upon  its  re- 
moval; but  it  should  not  be  extracted  at  this  time. 

Leave  the  temporary  cuspid  in  position  until  all  of  the  other 
teeth  have  been  replaced.  If  the  order  which  nature  has  mapped 
out  has  been  preserved,  an  even  set  of  teeth  will  result  in  almost 
every  instance.  If  the  order  has  been  interfered  with  in  the  least, 
the  patient's  mouth  is  placed  in  a  condition  where  gross  irregu- 
larities, faulty  occlusion,  and  great  disfigurement  is  almost  sure  to 
result.  Therefore  the  great  necessity  for  the  preserA^ation  of  na- 
ture's order  in  the  extraction  of  the  temporary  teeth.  It  is  the  one 
thing  to  be  looked  after  and  adhered  to  and  should  be  disregarded 
only  in  extreme  cases,  which  does  not  mean  merely  the  satisfaction 
of  the  ideas  of  parents.  The  operation  of  extracting  temporary 
teeth  is  simple.  If  we  have  carefully  looked  the  mouth  over  and 
decided  that  it  is  necessary  to  extract  any  tooth,  it  can  be  accom- 
plished with  almost  any  pair  of  forceps.  Great  care  should  be 
taken  not  to  take  too  deep  a  grasp  upon  the  tooth,  that  the  develop- 
ing permanent  tooth,  which  is  supposed  to  be  close  to  its  tem- 
porary predecessor,  may  not  be  injured  in  the  removal  of  the  tem- 
porary tooth.  It  is  also  advantageous  to  use  a  lance  separating  the 
gum  from  the  tooth  as  the  gum  at  or  near  the  neck  of  the  tooth 
frequently  adheres  quite  strongly  to  the  cementum.  By  using  the 
lance,  laceration  of  the  parts  is  avoided. 

When  there  is  nothing  left  but  the  separated  or  decayed  points 
or  unabsorbed  portions  of  roots,  it  is  best  to  remove  them  with  a 
root  elevator  or  chisel. 


CHAPTER  XLI. 

LOCAL  AND  REGIONAL  ANESTHESLi 

Definition.  Local  anesthesia  is  that  term  applied  to  the  results 
obtained  when  only  a  {-ireumscribed  part  of  the  body  is  rendered 
without  sensation. 


FiK-    144.  —  Horizontal   injection,     a  represents  place   of  puncturing  tlie   soft  tissues. 

Divisions  of  Local  Anesthesia  ai-e  s>irface  aiicstliesia,  iiiMlti-alion 
aii<-.sllicsi;i.  iiil r;i-al vcolar  ;iiicst licsia,  and  regional  anesthesia  (fre- 
quently called   foiidiictive), 

275 


276 


OPERATIVE   DENTISTRY 


Fig.  145.— Perpendicular  injection,     a  represents  place  of  puncturing  the  soft  tissues. 


Uses  in  Dentistry.  Local  anesthesia  when  rightly  practiced  and 
successfully  used  is  the  most  practical  anesthesia  for  exodontia 
minor  surgical  operations  about  the  mouth,  as  well  as  most  of  the' 
delicate  dental  operations  connected  with  pulps  of  teeth.    The  sue- 


LOCAL   AND   REGIONAL   ANESTHESIA 


277 


cess  of  local  anesthesia  is  based  on  a  working  knowledge  of  the  oral 
anatomy,  sernpulons  asepsis,  fresh  drugs  and  a  correct  technic  in 
their  use. 

Anatomy.  The  knowledge  of  anatomy  should  embrace  a  clear 
understanding  of  the  muscular  attachments,  the  position  of  the 
foramen  and  a  knowledge  of  the  position  of  the  trigeminal  nerve 
with  its  complete  ramifications. 

Cocaine.  For  many  years  cocaine  has  been  almost  universally 
used  by  the  dental  profession  as  the  principal  local  anesthetic.    Its 


Fig.  146.— Drawing  representing  the  positions  of  needles  in  local  anesthesia,  j^,  position 
for  subperiosteal  injection  for  surgical  anesthesia;  B,  intra-alveolus  injection.  This  will  re- 
sult in  surgical  and  sometimes  dental  anesthesia.  This  injection  is  subject  to  very  severe 
criticism  due  to  the  liability  of  the  introduction  of  infection.  C,  intra-alyeolar  injection.  Ihis 
will  result  in  dental  anesthesia  and  quite  frequently  surgical  anesthesia  on  the  side  towara 
which  the  injection  is  made. 


toxicity  was  not  clearly  understood  at  the  beginning  and  thus  oc- 
curred overdosing  particularly  with  stale  solutions.  It  has  been 
fully  demonstrated  that  some  individuals  could  stand  heavy  doses 
without  showing  systemic  ill  effects,  while  death  would  result  in 
other  ca.ses  where  only  a  small  dose  had  been  u.sod.  For  these  rea- 
sons the  profession  has  been  hiuiling  a  substitute.  That  substitute 
seems  to  have  been  found  in  novocain. 

Novocain  is  ('(iiial  to  cocaine  in  anesthesia  ])rodu(*ing  power.     It 


278 


OPERATIVE   DENTISTRY 


is  relatively  non-toxic.  It  is  particularly  non-irritating  even  on 
the  most  delicate  tissues.  It  is  easily  combined  with  suprarenin, 
and,  so  combined,  does  not  loose  its  anesthesia  producing  power. 
Neither   does   it   affect   the   action   of   the   suprarenin.      It   can   be 


Fig.    147. — First   ijosition   in    the   mandibular   injection. 


boiled  for  the  purpose  of  completing  sterilization.  Novocain  is  a 
non-habit  producing  drug,  and,  as  claimed  by  the  manufacturers, 
is  derived  from  an  entirely  different  source  than  cocaine,  to  which 
it  is  in  no  way  related.  The  general  effects  upon  the  system  af- 
ter it  has  been  absorbed  are  scarcely  perceptible.  Neither  the  cir- 
culation nor  the  respiration  suffers  and  the  blood  pressure  is  not 


LOCAL   AND   REGIONAL   ANESTHESIA 


279 


iiici-eased.     From  experiiueiits  it  has  been  found  to  be  only  one- 
seventh  as  toxic  as  cocaine. 

Doses.     The  best  solution  for  dental  uses  is  probably  the  two 


Pig    148— Second  position  in  the  mandibular  injection.     This  position  is  taken  for  the  deposit 
of  the  anesthesia  for  the  lingual  nerve. 

per  cent  solution  for  both  the  inliltration  and  the  regional  nietbods. 
The  iiiaximurii  dose  of  a  two  per  cent  solution  is  twenty-four  cubic 
ceiitiiiioters.  Such  a  quantity  would  never  be  called  for  in  any 
dental  operation. 


280 


OPERATIVE   DENTISTRY 


Suprarenin  is  added  to  contract  the  capillaries  and  prevent  ab- 
sorption and  infiltration  into  the  tissues  beyond  the  field  of  opera- 
tion, thereby  increasing  the  duration  and  strength  of  the  anesthesia. 
It  is  also  added  in  certain  cases  to  decrease  the  flow  of  blood. 


Fig.    149. — Third   position   for   the   mandibular   injection. 


Dosage  of  Suprarenin.  Difeering  from  the  amount  of  novocain 
used  the  suprarenin  should  be  varied  for  individual  cases.  In  fact 
it  has  probably  been  the  practice  of  surgeons  to  use  too  strong  a 
solution  of  suprarenin  in  their  local  injections. 

Preparing  the  Solution.     In  a  dissolving  cup,  place  a  tablet  of 


LOCAL    AND    REGIONAL   ANESTHESIA 


281 


novocain  and  siiprarenin  to  which  add  Ringer's  solution  Q.  S.  to 
make  a  two  per  cent  solution  of  the  novocain.  Boil  over  the  open 
flame  for  one-half  minute  to  sterilize. 


Fig.   150.  — Fourth  and  last  position  for  the  mandibular  injection. 


Ringer's  Solution  is  made  as  f()]h)ws:  Ringer's  ta])lots;  sodium 
chloride,  0.050  gt;itii;  calcium  chloi-ide,  0.004  gram;  potassium 
chloride,  0.002  gram.    Dissolve  leii  tablets  in  100  cubic  centimeters 


^82 


OPERATIVE    DENTISTRY 


of  aqua  dest.  Sterilize  by  boiling  and  put  in  bottle  double  corked 
to  be  ready  for  use  when  needed. 

Stale  solutions  of  novocain  and  suprarenin  should  not  be  used. 
It  should  be  mixed  fresh  for  each  operation.  It  should  not  come  in 
contact  with  anything  but  the  boiling  cup  and  the  syringe  and 
should  not  be  left  longer  than  necessary  in  either  of  these. 

Care  of  Novocain  Tablets.  The  tablets  should  not  be  touched 
with  the  hands  and  should  be  kept  in  a  bottle,  rubber-stoppered. 
The  solution  should  be  as  clear  as  water  and  discarded  as  soon  as 
it  shows  a  light  pink  color. 


Fig.   151. — A  very  clear  and  easy  case  with  the  needle  in  the  best  position  for  the 
mandibular  injection. 


Surface  anesthesia  is  anesthesia  produced  by  topical  application. 
The  method  is  of  advantage  upon  mucous  membranes,  as  they  ab- 
sorb the  solution  rapidly.  The  effect  is  generall}^  not  deep.  How- 
ever, applied  to  the  gum  it  is  usually  sufficient  for  fitting  bands 
and  crowns  or  the  finishing  of  fillings  at  the  gingival  margin.  A 
pellet  of  cotton  saturated  with  a  tAventy  per  cent  solution  of  novo- 
cain and  packed  on  the  floor  of  the  nasal  cavity  over  the  incisor 
teeth  will  many  times  anesthetize  the  incisors  of  the  respective  side 


LOCAL   AND   REGIONAL   ANESTHESIA 


283 


sufficient  for  operations  upon  the  dentine  and  even  for  pulp  extir- 
pation. 

Infiltration  Anesthesia  is  the  method  whereby  anesthesia  is  pro- 
duced by  injection  of  the  tissues  about  the  nerve  endings.    The  suc- 


Fig.  152. — This  represents  a  difficult  case  where  the  lingula  is  almost  entirely  wanting  and 
the  needle  has  entered  the  sulcus  too  low  and  may  yet  l)e  engaged  in  the  tissues  of  the  external 
pterygoid  muhcle  which  it  must  have  penetrated  to  reach  this  positicHi. 

ce.ss  of  the  methotl  dcjx'iids  upon' the  tlvorouf^liness  witli  wliich  the 
tissues  to  be  operated  upon  are  infiltrated.  Tf  any  nerve  endinjjs 
are   missed   only   partial    success     is    ohliiincd.       T\iv     infillr-ition 


584 


OPERATIVE   DENTISTRY 


method  is  of  advantage  in  the  extraction  of  non-vital  teeth,  roots 
and  parts  of  roots.  It  is  the  best  method  for  the  extraction  of  all 
deciduous  teeth  and  roots.  This  method  is  used  for  any  of  the 
teeth  in  the  maxilla,  but  the  greatest  success  is  with  the  single- 


Fig.   153. — The  same  mandible  shown  in  Fig.  152  with  the  needle  passed  to  position  suiificiently 
high  to  be  above  the  lingula  represented  by  a. 

rooted  teeth.  With  the  mandible  the  infiltration  method  is  of  little 
service  posterior  to  the  cuspids  when  vital  teeth  are  involved. 
There  are  but  two  injections  to  consider  with  the  infiltration  method 
in  dental  operations,  namely,  the  horizontal  and  perpendicular. 


LOCAL   AND   REGIONAL   ANESTHESLA. 


285 


The  Horizontal  Injection  for  the  bicuspids  and  molars  excepting 
the  third  molar.  By  this  method  several  teeth  may  be  injected 
with  only  the  one  puncture  of  the  tissues,  thereby  materially  less- 
ening the  liability  of  infection.  This  injection  is  contraindicated 
in  diseased  tissue. 

The  Perpendicular  Injection  is  applicable  for  all  single-rooted 
teeth.  The  needle  should  generally  be  inserted  just  below  the  gum 
margin  and  the  point  carried  lingually  or  buccally  of  the  apex  of 


Fig.  154. — This  is  a  mandible  which  belongs  to  a  class  on  which  it  is  very  hard  to  give  a 
mandibular  injection.  Note  that  the  internal  oblique  line  is  continuous  up  to  the  sigmoid 
notch.  The  lingula  (a)  is  one  cm.  higher  than  normal  and  is  only  about  four  mm.  back  of 
the  internal  oblir|uc  line.  Conditions  like  this  possibly  explain  why  even  the  most  expert 
sometimes  do  not  get  results  upon  first  attempt. 

the  tooth  the  anesthesia  of  which  is  desired.  The  solution  is  in- 
jected without  pressure  and  the  needle  does  not  go  sub-periosteal 
as  in  distinction  from  the  intra-alveolar.  The  quantity  of  solu- 
tion to  inject  is  about  one  and  a  half  cubic  centimeters  for  the 
horizontal  injection  and  about  one  cubic  centimeter  for  the  per- 
pendicular. A  one-inch  needle  of  small  size  is  best  suited  for  all 
infiltration  work. 

Intra-alveolar  Anesthesia  has  for  its  object  the  blocking  of  the 


286 


OPERATIVE   DENTISTRY 


nerve  before  it  enters  the  pulp  of  an  individual  tooth  by  injecting 
deeply  into  the  alveolus.  There  are  two  injections  in  this  method. 
They  are  the  pericemental  and  the  subperiosteal,  or  intraosseous. 

Tlie  Pericemental  Injection  has  been  the  most  widely  used  of  all 
the  methods  of  local  anesthesia  up  to  this  time,  for  the  reason  that 
it  requires  the  minimum  amount  of  the  drugs  used.    This  is  a  point 


Fig.  155.- — First  and  ideal  position  for  giving  the  mental  injection,  a  represents  the  posi- 
tion of  puncturing  the  soft  tissues.  With  fleshy  patients  the  syringe  barrel  will  of  necessity 
have  to  be  more  anterior. 


of  great  importance  in  the  use  of  cocaine.  However,  with  the  ad- 
vent of  novocain  the  method  will  be  used  less  frequently,  owing 
to  the  liability  of  infection.  The  method  has  been  useful  in  sur- 
gery, in  extracting  teeth,  due  to  the  accompanying  infiltration  of 
surrounding  tissues.  The  needle  should  be  short,  say  one-fourth 
of  an  inch,  and  of  twenty-eight  or  twenty-nine  gauge. 


LOCAL    AND    REGIONAL    ANESTHESIA 


287 


Tlie  Suh-periosteal  Injection  in  intra-alveolar  anesthesia  is  of  the 
greatest  use  in  operating  upon  vital  dentine  and  pulp  extirpation. 
The  needle  should  be  short  and  stocky,  twenty  or  twenty-two  gauge. 
It  is  inserted  beneath  the  periosteum  and  even  into  the  alveolar 
process  itself,  as  near  as  possible  to  the  apical  foramen  of  the 
tooth  to  be  operated  upon.     Considerable  force  is  used  in  both  of 


Fig.   156. — Second  position  for  giving  the  mental  injection,  showing  the   linger  compressing 
the  tissues  over  the  needle  inside  of  the  mouth  to  facilitate  injecting  tl>e  canal. 


the   intra-alveolar   injections   in   coiinlcr   distindion    of   all    of  the 
other  methods  of  locjil  anesthesia. 

Regional  Anesthesia  Conductive  Anesthesia  is  sliietly  a  neive 
blocking  process  whereby  a  region  of  llie  desired  e.xlent  is  anes- 
thetized. The  method  is  not  new^,  having  been  ])rac1iced  more  or 
less  since  the  latter  eighties,  but  has  received  a  great  impetus,  due 


288  OPERATIVE   DENTISTRY 

lo  the  production  of  an  agent  like  novocain  which  is  comparatively 
safe  for  general  practice.  Regional  anesthesia  is  by  no  means 
limited  to  the  field  of  dentistry,  but  its  use  is  as  broad  as  the  field 
of  surgery  on  mankind,  as  well  as  that  on  the  lower  animals.  The 
surgeon  has  but  to  know  his  anatomy  to  be  able  to  render  a  region 
as  void  of  sensation  as  though  the  part  had  been  amputated  from 
the  body.  For  instance,  the  arm  is  now  operated  on  without  pain, 
even  to  amputation,  by  surrounding  the  axillary  nerve  with  a 
puddle  of  a  two  per  cent  solution  of  novocain  with  suprarenin, 
reached  with  a  needle  in  the  top  of  the  shoulder  posterior  to  the 
clavical  and  internal  and  anterior  to  the  scapula.  Aside  from  the 
completeness  of  the  anesthesia  obtained,  regional  anesthesia  has 
to  recommend  it  the  fact  that  the  injection  is  made  far  from  the 
field  of  operation,  which  is  many  times  undergoing  pathological 
changes  often  due  to  bacterial  invasion.  About  the  face,  we  have 
seven  separate  and  distinct  nerve  blocking  operations  for  regional 
anesthesia.  The  injections  are;  Gasserian  ganglion,  Spheno-maxil- 
lary,  Pterygo-mandibular,  Mental,  Infra-orbital,  Zygomatic,  and 
Posterior  and  Anterior  palatine. 

The  Gasserian  and  Spheno-maxillary  Injections  are  employed  for 
major  surgical  operations  about  the  face  and  will  be  passed  over 
by  simply  mentioning  them,  as  the  strictly  operative  dentist  will 
have  no  need  to  employ  them.  However,  the  remaining  five  injec- 
tions are  of  vital  interest  to  the  general  practitioner  of  dentistry 
and  will  be  taken  up  in  the  order  given. 

Pterygo-Mandibular  Injection  has  for  its  object  the  blocking  of 
the  nerve  supply  to  the  lateral  half  of  the  mandible  and  the  im- 
mediate overlying  tissues. 

Technic  of  Injection.  Palpate  the  posterior  molar  triangle  hav- 
ing first  sterilized  the  immediate  field  of  puncture  with  campho- 
phenique.  Then  find  the  internal  oblique  line.  Puncture  the  tis- 
sues over  its  inner  edge,  using  a  forty-five  millimeter  iridio-platinum 
needle,  one  centimeter  above  the  plane  of  the  inferior  teeth  with 
the  barrel  of  the  syringe  resting  on  the  occlusal  surfaces  of  the 
bicuspids  of  the  opposite  side,  as  shown  in  Fig.  147.  Push  the 
needle  point  four  or  five  millimeters  into  the  tissues.  Now  swing 
the  syringe  to  the  position  shown  in  Fig.  148  for  the  lingual  nerve. 
Again  swing  the  syringe  into  the  position  shown  in  Fig.  149.  Push 
the  needle  into  the  tissues,  closely  following  the  inner  surface  of 
ramus  for  a  distance  of  about  two  centimeters  in  all  (see  Fig.  150), 
varying  with  the  size  and  age  of  the  patient.     To  follow  the  inner 


LOCAL    AND    REGIONAL    ANESTHESIA 


289 


Fig.  I37. — Position  of  needle  in  giving  the  infra-orbital  injection,  o  represents  the  place 
of  puncturing  the  soft  tissues.  If  it  is  desired  to  accompany  this  injection  with  the  perpen- 
dicular infiltration  injection,  the  soft  tissues  should  be  punctured  midway  between  the  point 
marked  a  and  the  gingival  margin  of  the  gum. 

surface  of  the  ramus  will  necessitate  the  swingin<>:  of  the  syringe 
to  the  median  line  as  the  needle  proj^resses.  It  is  very  essential 
that  the  needle  passes  into  the  sulfus  iiiandihularis,  above  the 
lingual,  or  el.se  it  will  pa.ss  over  this  int.i  llic  pici-ygoid  muscle,  of- 


290  OPERATIVE  DENTISTRY 

ten  resulting  in  false  unilateral  ankylosis,  generally  temporary, 
but  sometimes  more  or  less  permanent  and  always  to  be  avoided. 
If  anesthesia  of  only  the  pulps  of  the  teeth  is  desired,  the  special 
part  of  the  injection  for  the  lingual  nerve  should  be  omitted,  as 
there  is  less  liability  of  injecting  bundles  of  muscle  fibers.  In  case 
injection  is  made  for  surgical  purposes,  as  the  extraction  of  the 
first  molar  and  bicuspid,  an  infiltration  injection  had  best  be  made 
buccal  to  the  tooth  or  teeth  to  be  extracted  to  include  the  descend- 
ing branch  of  the  buccal  branch  of  the  third  division  of  the  fifth, 
which  is  given  off  just  above  the  pterygoideus  internus  and  ener- 
vates the  soft  tissues  of  the  biscuspids  and  molars  buccally.  An- 
esthesia occurs  in  fifteen  to  twenty  minutes  and  lasts  about  one 
hour,  sometimes  longer.  If  longer  anesthesia  is  desired,  the  amount 
of  the  injection  is  to  be  increased  up  to  four  cubic  centimeters. 

The  first  sign  of  anesthesia  is  the  numbness  of  the  side  of  the 
tongue  if  the  injection  for  the  lingual  nerve  has  been  included  and 
of  the  lip  above  the  mental  foramen  on  that  side.  These  are  the 
signs  of  a  successful  injection  and  occur  in  a  very  short  time,  yet 
the  deepest  state  of  the  anesthesia  may  not  work  back  to  the  pos- 
terior molars  for  twenty  to  thirty  minutes,  as  frequently  happens 
with  operations  for  the  extraction  of  lower  third  molars. 

Mental  Injection.  The  mental  injection  is  made  with  a  one  or 
two  centimeter  needle  passed  as  shown  in  Fig.  155.  The  operator 
should  compress  the  mucous  membrane  and  tissues  over  the 
foramen.  When  the  needle  is  felt  under  the  finger  (see  Fig.  156) 
one  cubic  centimeter  should  be  injected  while  pressing  which  will 
direct  the  solution  through  the  foramen  into  the  mandibular  canal, 
anesthetizing  the  first  bicuspid,  cuspid  and  incisors  of  the  respec- 
tive side. 

Infra-Orbital  Injection.  This  injection  is  made  in  the  same  way 
as  that  described  for  the  mental  foramen,  using  the  same  length  of 
needle  and  one  cubic  centimeter  of  the  solution.  Dental  and  surgi- 
cal anesthesia  is  obtained  in  the  bicuspids,  cuspid  and  incisors  of 
the  respective  side. 

Zygomatic  Injection.  The  long  needle  is  inserted  over  the  roots 
of  the  second  superior  molar  progressing  upward,  backward  and 
inward,  depositing  some  of  the  solution  as  the  needle  progresses, 
until  the  position  of  the  needle  is  as  shown  in  Fig.  158  where  the 
last  of  the  solution  is  deposited,  in  all  two  cubic  centimeters.  This 
injection  will  reach  the  posterior  superior  alveolar  nerve  and  the 
middle  superior  alveolar  in  case  it  is  given  off  before  the  maxillary 


LOCAL   AND   REGIONAL   ANESTHESIA 


291 


Fig.    158.— I-inal   position    of   the   needle   in    giving   the   zygomatic   injection,      a   represents   the 
place  of  puncturing  the  soft  tissues. 


nerve  enters  the  iiifi-a-orl)it;il  canal.  It  is  many  times  advisable  to 
add  to  this  the  horizontal  infilti'ation  injection  as  shown  in  Fig.  144 
to  reach  the  anterior  superior  alveolar,  the  branches  of  which 
anastojHose  with  the  branches  of  the  middle  alveolar.  This 
zvfroniatic  injection  especially  when  assisted  by  the  horizontal  in- 


292  OPERATIVE   DENTISTRY 

jection  will  give  dental  and  surgical  anesthesia  of  the  biseuspids 
and  molars  of  the  respective  side. 

Palatine  Injections.  The  needle  is  inserted  above  the  gingival 
margin  of  the  mesial  part  of  the  third  molar  for  the  posterior 
palatine  and  passed  upward  and  backward  to  the  palatine  process, 
injecting  one-third  of  a  cubic  centimeter.  For  the  anterior  pala- 
tine the  needle  is  inserted  lingually  and  above  the  gingival  margins 
of  the  superior  central  incisors  and  passed  upward  and  backward 
to  the  anterior  palatine  canals,  depositing  one-third  of  a  cubic 
centimeter.  These  injections  will  anesthetize  the  palatal  part  of 
the  gums  for  surgical  work,  as  extractions. 

In  Conclusion.  Always  use  the  simplest  method  that  will  be 
successful.  Do  not  inject  pathological  tissue.  Avoid  infection. 
Use  only  fresh  solutions.  Do  not  inject  muscle  tissue.  Use  a  solu- 
tion that  is  isotonic.  Attempt  regional  anesthesia  only  after  care- 
ful study  and  preparation. 


CHAPTER  XLII. 
THE  USE  OF  FUSED  PORCELAIN  IN  FILLING  TEETH. 

Definition.  A  porcelain  inlay  is  a  filling  made  of  dental  porce- 
lain and  retained  in  position  by  cement. 

A  Dental  Porcelain  is  a  solidified  mass  of  silicious  substances 
suspended  in  a  flux  of  fused  silicate. 

Composition.  Dental  porcelain  is  composed:  First,  of  the  basal 
ingredients  which  are  refractory,  as  silex,  kaolin,  and  feldspar.  Sec- 
ond, fluxes  used  to  increase  the  fusibility.  Those  in  common  use  are 
sodium  borate,  or  borax,  (NaoB^O-),  sodium  carbonate  (NagCog), 
and  potassium  carbonate  (K2CO3).  Third,  metals  and  oxides  used  as 
pigments. 

Silex  (SiOo)  is  the  oxide  of  silicon.  It  is  an  infusible  substance, 
insoluble  except  in  hydrofluoric  acid  and  is  used  to  give  strength  to 
the  porcelain.     It  gives  it  more  translucent  appearance. 

Kaolin  [Al^(SiOj3.4H20]  is  the  silicate  of  aluminum.  It  is  added 
to  the  porcelain  to  give  stability,  and  permits  unfused  porcelain  to 
be  molded  and  carved  in  the  shaping  of  the  contour. 

Feldspar  [KoOAlo03(  8100)6]  is  the  double  silicate  of  aluminum 
and  potassium.  It  forms  over  eighty  per  cent  of  the  basal  mass  of 
porcelain  and  adds  translucenc3\ 

Pigments.  The  various  shades  and  colors  in  porcelain  are  pro- 
duced by  the  addition  of  precipitated  gold,  platinum,  purple  of 
cassius,  oxides  of  cobalt,  titanium,  iron,  uranium  and  silver,  pro- 
ducing  the   colors  of  red,  yelloAV,  blue,   green,   broAvn   and   gray. 

High-Fusing  Porcelain.  By  high-fusing  porcelain  is  meant  a 
porcelain  that  requires  five  minutes  or  more  to  fuse  at  a  tempera- 
ture exceeding  the  fusing  point  of  pure  gold. 

Low-Fusing  Porcelain.  This  is  a  porcelain  that  requires  less  than 
five  minutes  to  fuse  at  a  temperature  not  exceeding  the  fusing 
point  of  pure  gold.  This  division  is  one  of  creation  by  the  manu- 
facturers and  commonly  accepted  by  the  profession.  However  the 
distinction  is  only  relative  as  porcelain  has  no  definite  fusing  point, 
as  any  enamel  ov  tooth  foundation  body  may  be  fused  on  a  matrix 
fif  purf  yold  ii'  ciKjiiifl)  time  is  yivoii  to  the  fusing  pi'ocess. 

Effects  of  Fusing  at  Lower  Temperatures  and  a  Longer  Time. 

A  more  homogeneous  mass  is  produced. 

A  more  characteristic  color  is  maintained. 

A  less  friable  filling  is  produced. 

293 


294  OPERATIVE  DENTISTRY 

A  High-Fusing  Porcelain  May  Be  Made  Low-Fusing  by  repeated 

fusing  and  grinding. 

In  Building  a  Filling  by  Layers  the  first  layer  should  be  fused 
to  a  state  of  high  biscuit  otherwise  the  process  of  fusing  the  sub- 
sequent layers  will  over-fuse  the  first. 

High  Biscuit  Fuse.  Heating  the  porcelain  sufficient  to  obtain 
shrinkage,  but  not  enough  to  glaze. 

Fine  Grinding.  The  more  finely  porcelain  is  ground  the  lower 
the  fusing  point  from  the  same  formula  and  the  greater  the  shrink- 
age. 

Size  of  Mass.  The  larger  the  mass  the  greater  the  length  of 
time  required  to  fuse. 

Amount  of  Flux.  The  more  flux  a  porcelain  contains  the  great- 
er the  liability  to  bubble,  which  liabilitj''  increases  as  the  tempera- 
ture is  raised. 

Shrinkage  in  Fusing.  High  fusing  porcelains  shrink  from  fif- 
teen to  twenty-five  per  cent.  Low  fusing  porcelain  shrinks  from 
twenty  to  thirty-five  per  cent. 

Spheroiding.  All  porcelains  have  a  great  tendency  to  spheroid 
when  over-fused. 

A  Basal  Body  is  porcelain  composed  of  basal  ingredients  and  the 
pigments. 

A  Foundation  Body  is  one  composed  of  basal  ingredients  to  which 
has  been  added  a  flux  to  increase  fusibility,  and  has  been  ground 
less  fine  than  enamel  body  to  raise  fusing  point  and  give  stability 
as  to  form. 

An  Enamel  Body  is  a  basal  body  which  has  been  more  finely 
ground  and  to  which  there  has  been  added  more  flux  to  increase 
fusibility. 

The  Advantages  of  the  Porcelain  Inlay.  When  skillfully  made 
they  more  nearly  harmonize  with  tooth  structure  in  appearance. 
Thermal  changes  do  not  readily  affect  the  pulp  in  vital  cases  as 
porcelain  is  not  as  good  a  conductor  as  metal. 

Margins  of  cavities  well  filled  with  porcelain  are  not  readily  at- 
tacked by  caries,  as  cement  dissolves  out  of  the  margin  to  a  depth 
only  equal  to  the  breadth  of  the  line  exposed.  Patients  are  relieved 
of  sitting  with  the  rubber  dam  in  position  for  protracted  periods. 

The  Disadvantages  of  the  Porcelain  Inlay.  The  friability  of 
porcelain  restricts  its  use  to  locations  removed  from  great  stress. 
It  is  necessary  to  omit  the  marginal  bevel  in  all  cavities,  as  the 


USE   OF   FUSED   PORCELAIN    IN   FILLING   TEETH  295 

edge  strength  of  porcelain  is  no  greater  than  full  length  enamel 
rods. 

The  Cavo-surface  Angle  should  be  that  which  the  cleavage  of 
the  enamel  gives,  or  about  a  right  angle.  Its  greatest  disadvan- 
tage is  the  fact  that  the  inlay  must  be  set  upon  unclean  walls  as 
the  whole  process  must  be  done  under  moist  conditions;  moisture 
being  necessary  to  maintain  the  color  of  the  teeth  while  trying  to 
imitate  their  shade.  This  prevents  the  placing  of  the  filling  upon 
freshly  cut  surfaces  M^hich  have  not  been  moistened,  the  greatest 
enemy  to  all  inlay  fillings. 

Another  disadvantage  is  that  the  retention  of  the  porcelain  de- 
pends upon  the  integrity  of  the  cement,  which  is  not  wholly  pro- 
tected at  the  margins.  While  porcelain  inlays  fit  the  cavity  from 
a  practical  standpoint,  the  fact  exists  that  they  never  exactly  fill 
the  cavity,  the  cement  taking  up  the  space  resulting  from  the  mis- 
fit, and  is  exposed  in  proportion  to  the  amount  of  existing  space 
at  the  margins. 

Indication  for  Porcelain  Filling'.  Porcelain  is  indicated  in  the 
following  : 

In  cavities  in  the  anterior  location  in  the  mouths  of  patients  who 
have  an  appreciation  for  esthetic  qualities  of  dental  operations. 

In  cavities  of  Class  One  Avhen  they  occur  in  defects  on  labial 
surfaces. 

In  cavities  of  Class  Three  when  much  of  the  labial  wall  is  gone 
and  rather  strong  lingual  wall  remains. 

In  cavities  of  Class  Four,  plan  three,  vital  teeth  with  rather 
thick  incisal  edge,  not  subjected  to  great  stress  in  articulation. 

In  cavities  of  Class  Four,  plan  one,  when  proximating  tooth  is 
not  in  position  as  when  the  missing  tooth  is  worn  upon  a  plate  or 
is  to  be  subsequently  replaced  with  a  crown  or  bridge. 

In  cavities  of  Class  Four,  plan  four,  in  upper  teeth  when  the 
lingual  surface  does  not  articulate. 

In  gingival  third  (Class  Five)  in  anterior  teeth  exposed  to  view 
when  patient  smiles. 

In  cavities  of  Class  Six  on  the  six  anterior  teeth,  when  the  porce- 
lain is  built  to  a  thickness  of  at  least  two  millimeters,  and  in  pulp- 
less  lower  molars,  restoring  the  entire  occusal  surface. 

Contraindications.  Porcelain  is  not  indicated  in  the  cavities  not 
i;bovc  mentioned,  and  in  all  locations  subject  to  great  stress  and 
where  good  access  form  is  difficult  to  obtain. 


CHAPTER  XLIII. 
PEEPARATION  OF  CAVITIES  FOR  PORCELAIN  INLAYS 

The  filling  of  teeth  with  porcelain  demands  some  change  in  the 
usual  and  accepted  form  of  cavity  preparation  for  other  materials. 

Access  Form.  Access  form  reaches  its  maximum  in  porcelain 
filling.  Even  greater  access  is  required  than  for  the  gold  inlay. 
Hence  preliminary  separation  should  be  practiced  with  all  proximal 
fillings,  before  forming  the  matrix,  and  generally  mechanical 
separation  is  of  advantage  when  setting  the  filling. 

Outline  Form  for  Porcelain  Inlays.  Outlines  must  be  extended 
to  regions  of  sound  enamel.  The  obtaining  of  full  length  enamel 
rods  supported  by  sound  dentine  is  imperative.  Extending  to  self- 
cleansing  margins  is  of  additional  advantage,  yet  not  so  impera- 
tive as  with  gold  filling,  as  secondary  decay  is  not  as  liable  to  take 
place  about  a  porcelain  filling. 

The  outline  should  not  follow  a  developmental  groove  nor  cross 
a  ridge  at  its  extreme  eminence.  Sharp  angles  in  outline  should 
be  avoided.  Extension  for  prevention  as  applied  to  the  embrasures 
is  not  as  great  as  with  metal  fillings. 

Extension  for  Resistance  to  Stress  at  margins  is  more  essential 
than  with  gold,  due  to  the  friability  of  porcelain  margins. 

Resistance  Form  for  Porcelain  Inlays.  The  rules  for  flat  seats 
for  all  fillings  apply  equally  to  porcelain  fillings.  The  use  of  the 
step  in  Class  Four  is  essential  to  give  added  resistance  to  the  tip- 
ping strain.  Margins  should  be  extended  to  locations  less  fre- 
quented by  the  crushing  strain. 

Retention  Form  for  Porcelain  Inlays.  Maximum  retention  form 
is  required  in  all  directions  except  one,  until  the  matrix  has  been 
formed  and  the  filling  made  ready  for  setting,  when  retention 
should  be  added  in  the  remaining  direction. 

Acute  line  and  point  angles  should  be  avoided;  all  angles  being 
rounded  angles  until  the  matrix  is  formed. 

Convenience  Form  for  Porcelain  Inlays.  The  filling  of  teeth 
with  porcelain  requires  more  cutting  for  convenience  form  than 
for  any  other  method.  This  fact  makes  such  fillings  contraindi- 
cated  many  times,  due  to  the  great  loss  of  tooth  substance  neces- 
sary to  properly  form  the  matrix  and  introduce  the  filling.  Pre- 
vious separation  Avill  overcome  this  cutting  to  a  large  extent  with 
this  as  well  as  other  fillings. 

296 


PREPARATION  OF  CAVITIES  FOR  PORCELAIN  INLAYS 


297 


Finish  of  Enamel  Walls.  All  finishing  of  enamel  avails  must  be 
completed  before  forming  the  matrix.  The  cavo-surface  angle 
should  be  a  right  angle  as  the  strength  of  fused  porcelain  is  about 
equal  to  supported  enamel  margins.  If  a  bevel  angle  exists  it 
should  be  deeply  buried. 

Toilet  of  the  Cavity.  This  is  attended  to  the  same  as  with  other 
inlay  fillings  before  forming  the  matrix. 

Another  Cavity  Toilet  is  necessary  just  before  setting  the  in- 
lay. This  consists  in  washing  the  cavity  with  chloroform  to  dis- 
solve any  oily  substances  adhering  to  the  cavity  walls.     This  is 


Fig.  159. — Cavity  preparation  for  a  Class  Two  porcelain  inlay,  non-vital  case  with  the 
porcelain  occupying  a  portion  of  the  pulp   chamber. 

followed  Avith  absolute  alcohol  and  moderately  dried.  Excessive 
desiccation  is  not  required  and  in  fact  should  not  be  practiced  as 
the  integrity  of  the  cemental  substance  in  the  enamel  is  injured 
and  liability  to  marginal  checking  increased. 

Preparation  of  Cavities  of  Class  One.  Defects  in  enamel.  Porce- 
lain is  indicated  in  cavities  on  tlie  labial  surfaces  of  the  six  an- 
terior, due  to  faulty  enamel.  These  are  shown  as  small  orifices 
in  the  enamel  surface,  generally  rounded  in  form,  and  is  the  result 
of  imperfect  development.  The  cavity  should  bo  not  loss  than  two 
millimeters  in  width  at  its  narrowest  point,  as  a  smallor  cavity 
than  this  hinders  proper  working. 


298 


OPERATIVE   DENTISTRY 


Avoid  the  Exact  Circle  in  outline,  as  this  will  bewilder  the  oper- 
ator as  to  the  position  when  setting.  In  case  the  outline  is  so  near 
a  circle  as  to  make  position  questionable,  the  axial  wall  should 
have  a  small  rounded  pit  at  one  side  to  guide  the  operator  in  set- 
ting. 

The  Axial  Wall  should,  in  large  cavities,  be  the  miniature  of  the 
tooth  surface  in  which  it  occurs.  The  axial  wall  of  small  cavities 
should  have  a  rounded  groove  cut  around  the  entire  circumference. 

The  Surrounding'  Walls  should  meet  the  axial  at  an  obtuse  angle 
to  relieve  any  undercuts  before  the  matrix  is  formed.     When  the 


Fig.   160. — A   Class  Three  cavity  labial 
approach    for  porcelain   inlay. 


Fig.    161. — A  Class  Three  cavity  labial 
approach    for   porcelain   inlay. 


inlay  is  ready  to  set  give  the  cavity  retentive  form  by  making  the 
base  line  angles  acute. 

Cavities  in  Proximal  of  Bicuspids  and  Molars.  Class  Two.  Ex- 
perience has  taught  us  that  porcelain  is  not  indicated  in  this  class 
of  cavities.  Their  location  subjects  the  filling  to  extreme  crushing 
strain  which  porcelain  will  not  stand.  The  occlusal  surfaces  are  of 
an  irregular  shape  and  made  up  of  a  great  variety  of  forms  with 
surfaces  in  any  number  of  planes.  This  makes  the  right  angle 
cavo-surface  angle  demanded  in  porcelain  filling  improbable  and 
results  in  exposing  porcelain  margins  of  an  acute  angle.  (Fig. 
159  may  be  used.) 


PREPARATIOX  OF  CAVITIES  FOR  PORCELAIN  INLAYS 


299 


Cavities  in  Proximal  of  Incisors  and  Cuspids  Not  Involving-  the 
Angle.  Class  Three.  This  class  of  cavity  is  ideal  for  porcelain  in- 
lays and  is  by  far  the  most  sightly  filling  Avhen  properly  done. 

These  Cavities  Should  be  Divided  Into  Two  Classes  in  accord- 
ance with  the  three  different  lines  of  approach. 

First  division,  labial  approach;  second  division,  lingual  ap- 
proach. 


Fig.  162. — A  Class  Three  cavity  lingual  approach  for  porcelain  inlay. 


Labial  Approach,  This  approach  should  be  decided  upon  when 
any  considerable  amount  of  the  labial  enamel  is  to  be  replaced  and 
a  lingual  wall  is  possible.     (Figs.  IGO  and  161.) 

The  Gingival  Wall  should  be  extended  gingivally  to  include  all 
affected  enamel.  It  should  be  flat  axio-proximally  and  meet  the 
axial  wall  at  an  angle  slightly  acute.  It  should  meet  the  lingual 
wall  at  an  angle  slightly  obtuse. 

The  Axial  Wall  should  be  flat  ]al)io-]ingually  and  be  continu- 
ous from  the  axio-liiigual  line  angle  to  the  labial  cavo-surface  angle 
which  results  in  the  entire  removal  of  the  labial  wall.  This  wall 
should  meet  the  lingual  and  incisal  walls  at  an  acute  angle.  The 
incisal   lingual   line  angle   should   bo  slightly   obtuse.     This   results 


300 


OPERATIVE   DENTISTRY 


in  a  cavity  retentive  in  all  directions  except  to  the  labial  which 
gives  it  "draw"  in  this  direction. 

Lingnal  Approach.  The  whole  general  plan  is  reversed  result- 
ing in  the  retention  of  all  or  a  good  portion  of  the  labial  wall  and 
an  entire  absence  of  the  lingual  wall  resulting  in  the  draw  being 
to  the  lingual. 

To  Resist  the  Tipping  Strain  the  lingual  step  may  be  added. 
This  is  done  by  cutting  away  a  sufficient  amount  of  the  lingual  en- 
amel resulting  in  two  axial  walls.     One  will  face  the  proximal  and 


Fig.    163.- — A   Class   Four   cavity   incisal 
approach    for    porcelain    inlay. 


Fig.    164. — A   Class   Four,    plan   one,   inciso- 
proximal   approach   for   porcelain   inlay. 


the  other  the  lingual.  This  creates  a  line  angle  where  the  two 
walls  unite,  the  axio-axial  line  angle  which  should  be  a  rounded 
angle.  Just  before  setting  the  inlay  the  axial  wall  should  be  slight- 
ly grooved  next  to  the  surrounding  walls,  except  in  the  region  of 
the  incisal  point  angle. 

Cavities  in  Proximal  of  Incisors  and  Cuspids  Involving  the  Angle. 
Class  Four,  Plan  One.  This  plan  of  angle  restoration  may  be  suc- 
cessfully accomplished  with  porcelain  when  the  conditions  of 
stress  would  permit  of  this  plan  being  used  with  any  other  ma- 


PREPARATION  OF  CAVITIES  FOR  PORCELAIN  INLAYS 


301 


terial.  The  cavity  form  is  the  same  as  that  just  described  for  a 
gold  inlay. 

Proximal  Approach  May  be  Used  in  this  instance  under  some 
conditions.  The  incisal  approach  may  be  used  "when  excess  sepa- 
ration has  been  produced  a  little  greater  than  the  length  of  the  in- 
cisal line  angle,  as  "vvell  as  more  than  the  thickness  of  the  inlay 
measuring  from  contact  point  to  the  greatest  depth  of  the  axial 
wall,  "which  permits  the  filling  entrance  from  the  incisal. 

To  Break  the  Cement  Line  on  the  Incisal  Edge  a  rounded  groove 


Fig.   165. — A  Class  Four,  plan  two,   with  double  step  for  porcelain  inlay. 


should  l)e  made  fi'om  the  external  end  of  the  incisal  line  angle  to 
the  incisal  cavo-surface  angle. 

Plan  Two,  Class  Four,  is  suitable  for  porcelain  filling  provided 
the  material  will  stand  the  strain  at  union  of  step  and  cavity 
proper.    The  double  step  is  advised.     (Fig.  164.) 

Plan  Three,  Class  Four.  The  addition  of  the  lingual  step  makes 
many  angle  lestoiations  with  porcelain  practical,  as  the  tipping 
strain  can  be  well  provided  for  by  grooving  in  the  lingual  axial 
wall  next  to  the  distal  or  mesial  wall  according  to  whether  the 
cavity  is  distal  or  mesial.  The  cavity  should  be  so  shaped  that 
the  draw  is  directly  to  the  incisal.     The  gingival  wall  should  be 


302 


OPERATIVE    DENTISTRY 


flat  and  meet  both  axial  walls  at  an  acute  angle.  The  axio-labial 
line  angle  should  be  acute.  The  lingual  axial  wall  should  be  con- 
cave. The  axio-axial  line  angle  should  be  a  rounded  angle  and 
continue  out  to  the  incisal  cavo-surface  angle. 

Plan  Four,  Class  Four.  In  angle  restoration  the  creation  of  both 
incisal  and  lingual  steps  is  most  popular.  The  incisal  step  is  formed 
in  much  the  same  way  as  when  gold  is  to  be  used.  However  the 
pulpal  wall  should  be  placed  farther  from  the  incisal  edge  and 
be  laid  in  a  plan  less  acute  to  the  axial  wall  than  for  gold. 

The  angle  formed  by  the  junction  of  these  walls,  the  axio-pulpal 
angle,  should  be  rounded.  In  forming  the  lingual  step  the  enamel 
may  be  removed  entirely  to  a  level  of  the  gingival  wall,  or  it  may 
be  only  as  much  of  the  incisal  portion  as  may  seem  necessary  to 
strengthen  the  body  of  porcelain  in  the  incisal  region  and  resist 
the  tipping  strain. 


Fig.   166. — A   Class  Four,  plan  three,   for  porcelain  inlay. 


The  Double  Step  is  of  service  in  cases  where  there  has  been  ex- 
tensive loss  of  tooth  structure,  particularly  in  non-vital  cases. 
This  plan  results  in  a  gingival  wall  and  two  pulpal  walls ;  also  in 
two  short  axial  walls  placed  on  an  equal  number  of  levels.  The 
gingival  and  pulpal  walls  should  be  made  to  meet  the  axial  walls 
at  acute  angles.  Each  of  the  two  pulpal  walls  should  be  grooved 
from  the  connecting  axial  walls,  and  each  axial  wall  in  the  central 
portion  resulting  in  a  continuous  groove  from  the  gingivo-axial  line 
angle  to  the  incisal  edge.  This  cavity  has  draw  directly  to  the 
incisal. 

Cavities  Occurring-  in  the  Gingival  Third  of  Class  Five.  Labial 
cavities  in  the  gingival  third  are  favorite  places  for  porcelain  and 
should  to  a  large  measure  displace  gold.  If  the  cavity  extends  be- 
neath the  gum  line,  the  gum  should  be  forced  from  position  by 


PREPARATION  OF  CAVITIES  FOR  PORCELAIN  INLAYS 


303 


previous  packing  of  gutta-percha  or  cotton  saturated  with  chlora- 
percha. 

Outline  Form  should  be  the  same  as  for  other  filling.  The  axial 
vail  should  be  the  miniature  of  the  tooth  surface  wherein  the 
cavity  occurs.  The  gingival  Avail  should  be  flat  and  meet  the  axial 
at  an  acute  angle.  All  other  surrounding  walls  should  meet  the 
axial  at  slightlj'  obtuse  angles.  This  gives  a  cavity  with  draAV  to 
the  labial  alloAving  the  incisal  portion  to  saving  out  in  advance, 
the  inlay  going  to  place  gingival  first. 

This  hinge  movement  is  slight  but  constitutes  a  valuable  point 


^^^^L^      ^ 

Fig.    167. — Class   Five   cavities   for   porcelain    inlay. 

in  subsequent  retention.  Just  before  setting  the  inlay  the  axio- 
incisal  line  angle  should  be  sharpened  to  add  retention  foi-m.  In 
cases  where  the  decay  resulting  in  a  cavity  is  materially  TiorsesJioe 
in  form  the  cavity  may  be  filled  by  two  distinct  o])oiati()iis. 

This  is  accomplished  by  filling  the  cavity  with  cement  and  cut- 
ting out  one-half  and  filling  with  porcelain.  This  completed,  the 
other  half  is  cut  out  and  the  operator  then  proceeds  to  fill  that  por- 
tion.    This  rcsulls  ill  two  poi'fclain  fillings  with  cement  between. 

One  Point  Must  Be  Observed.  Tlie  fii-st  portion  of  porcelain 
will  necessarily  slightly  overlap  a  cement  Avail.  Before  setting, 
this  portion  of  the  inlay  mu.st  be  ground  at  the  expense  of  the  ex- 
ternal surface  of  the  filling  to  reverse  the  di-aw,  oi*  this  poi-tion  of 


304 


OPERATIVE   DENTISTRY 


the  remaining  cavity  will  be  found  with  an  objectionable  under- 
cut hard  to  manage. 

Restoration  of  a  Portion  of  the  Incisal  Edge.  The  general  out- 
line in  this  class  of  cavities  when  they  are  simply  a  notch  in  the 
body  of  the  tooth,  is  that  of  the  half  moon  when  viewed  either  from 
the  labial  or  the  lingual.  HoAvever  the  lingual  enamel  should  be 
removed  for  a  greater  distance  root-wise  resulting  in  a  lingual 
step  to  provide  against  the  tipping  strain.  The  pulpal  wall  should 
have  a  groove  mesio-distally  in  its  central  portion  and  extend  well 


Fig.   168. — Incisal  cavity  for  porcelain  inlay. 


up  along  both  mesial  and  distal  walls,  and  with  the  larger  cavities 
coming  out  to  the  cavo-surface  angle. 

Restoration  of  the  Entire  Incisal  Edge — Outline  Form.  The  en- 
amel is  chiseled  root- wise  till  it  is  firm  and  will  result  in  a  thick- 
ness of  porcelain  at  all  points  equal  to  at  least  two  millimeters. 

Retention  is  accomplished  by  the  addition  of  pins,  or  a  generous 
lingual  step,  or  both. 

In  vital  cases  where  pin  retention  is  to  be  used  there  should  be 
cut  a  V-shaped  groove  mesio-distally,    the    spreading    angles    of 


PREPARATION  OF  CA^^TIES  FOR  PORCELAIN  IXLAYS 


305 


which  should  come  just  short  of  the  dento-enamel  junction  labially 
and  lingually,  Mesially  and  distally  it  should  continue  to  the 
cavo-surface  angle.  A  pin  hole  should  then  be  bored  in  the  ex- 
treme ends  of  this  groove  not  a  great  distance  from  the  dento-en- 
amel junction  in  the  dentine  to  receive  the  pins.  AVhen  the  lingual 
step  is  to  be  added  the  enamel  on  the  lingual  is  removed  additional- 
ly to  a  distance  root-wise  at  least  equal  to  the  labial  exposure ;  also 
an  amount  of  dentine  sufficient  to  make  the  newly  created  axial 
wall  meet  the  two  pulpal  walls  at  right  angles.  If  pins  are  to  be 
added  the  holes  should  be  bored  in  the  floor  of  the  pulpal  wall 
nearer  the  labial  surface. 

In  Pulpless  Six  Anterior  Teeth  the  pulp  chamber  may  be  rounded 
out  and  porcelain  so  baked  as  to  form  a  post  of  porcelain  for  re- 
tention. 


Fig.   169. — A  Class  Six  cavity  using  pin  anchorage  for  porcelain  inlay.     This  plan  is  also 
used  with  the  gold  inlay. 


Pulpless  Molars  are  ti-eated  in  the  same  way. 

Treatment  of  Teeth  With  Malformed  Enamel.  The  major  por- 
tion or  all  of  the  enamel  can  he  successfully  replaced  with  porce- 
lain. 

The  enamel  is  removed  to  the  desired  point  resulting  in  a 
gingival  wall  entirely  encircling  the  tooth.  Sufficient  dentine  is 
removed  in  the  incisal  region  to  render  the  largest  girth  at  the 
gingivo-axial  line  angle  which  is  continuous  around  the  tooth.  This 
leaves  a  peg-.shaped  bod}'  of  dentine  over  which  the  porcelain  is 
telescoped.  The  method  is  termed  the  jacket  crown  and  the  method 
of  construction  and  setting  is  fully  described  in  the  Avritings  of 
others  (*n  r-rown  work. 


CHAPTEE  XLIV. 

THE  CONSTRUCTION  AND  PLACING  OF  A  PORCELAIN 

INLAY 

Following  tlie  completion  of  cavity  preparation  the  next  step  in 
porcelain  inlay  filling  is  the  formation  of  a  matrix. 

A  Matrix  is  a  thin  piece  of  metal  shaped  to  the  cavity  form  in 
which  the  porcelain  is  fused. 

Matrix  Material.  The  matrix  materials  in  common  use  are  pure 
gold,  pure  platinum  and  platinized  gold.  Pure  gold  and  platinized 
gold  can  be  used  only  with  Avhat  is  termed  low  fusing  bodies, 
while  pure  platinum  can  be  used  with  either  high  or  low  fusing 
bodies.  Gold  is  more  easily  shaped  to  cavity  form,  but  tears  more 
easily  and  does  not  hold  its  shape  as  well  after  burnishing. 

Thickness  of  Foil.  The  most  popular  thickness  of  platinum  foil 
to  be  used  in  the  construction  of  a  matrix  is  1-1,000  of  an  inch. 
Thicker  than  this  is  difficult  to  manipulate,  while  the  thinner  foils 
tear  too  easily,  and  are  more  liable  to  distortion  during  the 
processes  of  building  and  fusing. 

Annealing  of  Matrix  Material.  This  is  best  accomplished  by 
placing  the  entire  sheet  of  material  as  it  comes  from  the  supply 
house  in  the  electric  oven  and  bringing  it  to  the  desired  tempera- 
ture before  cutting  off  the  piece  desired  for  the  case  in  hand.  Pure 
gold  and  platinized  gold  should  be  brought  to  the  full  red  heat  or 
about  1,200°  or  1,300°  F.  Platinum  should  be  carried  up  as  high  as 
it  is  expected  to  carry  the  temperature  during  the  process  of  fusing 
and  held  there  for  two  or  three  minutes.  It  is  not  necessary  to  an- 
neal several  times  during  the  process  of  shaping  the  matrix. 

Methods  of  Forming  the  Matrix.  There  are  three  general 
methods  in  use  for  the  construction  of  a  matrix.  First,  burnishing 
directly  into  the  cavity.  Second,  swaging  over  an  impression  of 
the  cavity.     Third,  swaging  into  a  model  of  the  cavity. 

Each  has  its  advantage  in  different  cases  and  are  recommended 
by  all  porcelain  workers.  However,  the  combination  of  the  first 
and  second  methods  will  bring  good  results  and  is  the  method  re- 
quiring the  least  time. 

Technic  of  the  Combination  Method.  First  take  an  impression 
of  the  cavity.  If  the  cavity  is  large  it  is  best  to  use  modeling  com- 
pound, trimming  off  that  part  which  flares  out  over  the  external 

306 


CONSTRUCTION  AND  PLACING  OF  PORCELAIN  INLAY        307 

surface  of  the  tooth.  The  matrix  is  then  shaped  over  this  iinpres- 
sion  with  the  fingers,  using  the  soft  part  of  the  ball  of  the  thumb 
as  a  counter  die. 

The  most  prominent  parts  of  the  impression  will  represent  the 
deepest  portion  of  the  cavity  and  A\'ill  assist  in  causing  the  matrix 
to  reach  this  Avithout  tearing  which  is  accomplished  by  using  the 
impression  to  crowd  the  matrix  to  position.  The  impression 
should  be  removed  leaving  the  matrix,  Avhich  has  been  by  this 
means  partially  swaged,  in  the  cavity. 

The  Removal  of  the  Impression  Without  Carrying'  Away  the 
Matrix  is  accomplished  by  bending  the  portions  of  matrix  exposed 
above  the  cavo-surface  angle  aAvay  from  the  impression.  The 
matrix  should  not  be  burnished  down  onto  the  external  surface  of 
the  tooth  until  the  other  portion  has  been  made  to  thoroughly  con- 
form to  the  cavity  walls. 

"When  the  impression  has  been  removed  the  matrix  should  be 
thoroughly  burnished  to  all  cavity  walls  beginning  at  the  seat  of 
the  cavity  first.  This  burnishing  is  done  with  suitable  smooth- 
faced instruments,  keeping  moistened  chamois  skin  discs  between 
the  instrument  and  the  matrix. 

The  cavity  should  now  be  packed  with  damp  cotton  halls  crowd- 
ing the  matrix  ahead  of  them  to  every  part  of  the  cavity.  While 
this  cotton  is  in  position,  the  matrix  should  receive  thorough  burn- 
ishing at  the  cavity  margins  and  finally  be  turned  out  on  to  the  ex- 
ternal surface  of  the  tooth  a  distance  of  one-fourth  of  a  millimeter 
to  one  full  millimeter  in  all  locations  except  one,  Avhieli  may  l)e 
tAvo  or  three  millimeters. 

This  one  place  will  facilitate  liandling  during  the  process  of  fill- 
ing in  the  porcelain.  The  cotton  may  now  l)e  removed  and  gum 
camphf)!-  ()]"  gold  inlay  casting  wax  ci'ov\ded  into  the  cavity  over 
the  matrix,  filling  the  cavity  nearly  full  with  one  piece  of  nmterial 
packed  to  place  with  a  flat-faced  amalgam  burnisher  as  large  as 
the  cavity  Avill  admit. 

Removal  of  Matrix.  The  matT-ix  is  then  removed  from  the  cav- 
ity by  sticking  the  tine  of  an  cx])loi(r  into  the  body  of  the  cam- 
plior  or  wax  near  its  central  poiiioii.  The  matrix  and  wax  or 
camphor  still  on  the  tine  of  the  explorer  should  be  immersed  in 
alcohol  if  camphor  has  been  used  or  chloroform  if  Avax  has  been 
used,  which  will  immediately  loosen  the  tine  and  dissolve  the  ma- 
terial from  the  matrix,  aftei*  which  the  nialrix  shonld  be  picked  np 


308  OPERATIVE   DENTISTRY 

in  the  lock  tweezers  at  that  portion  where  the  metal  has  been  left 
to  extend  the  farthest  from  the  cavo-surface  angle. 

The  matrix  should  now  be  passed  through  the  alcohol  flame  when 
the  camphor  or  Avax  remaining  will  be  burned  off  leaving  no  ash. 

Wood  as  an  Impression.  In  simple  small  cavities  it  is  well  to 
shape  a  piece  of  soft  pine  (as  cork  pine)  to  proximately  fit  the  cav- 
ity. This  should  be  then  introduced  against  the  deepest  portion 
of  the  cavity  and  given  a  few  blows  from  the  mallet  which  will 
cause  the  wood  to  conform  to  the  floor  of  the  cavity.  This  should 
then  be  used  as  an  impression  and  the  matrix  forming  proceeded 
with,  as  described  when  modeling  compound  has  been  used.  The 
use  of  the  stick  with  modeling  compound  on  the  end  is  of  advan- 
tage in  large  deep  cavities  where  the  pulp  chamber  is  to  be  filled 
with  porcelain  in  place  of  metal  pin.  By  this  means  it  is  possible 
to  place  a  matrix  well  to  the  bottom  of  any  cavity  without  tearing, 
provided  the  walls  are  regular  and  have  the  proper  draw  devoid  of 
under  cuts. 

Taking  the  Spring-  Out  of  a  Matrix.  If  a  matrix  seems  to  retain 
"spring"  and  does  not  seem  to  lay  well  on  all  surfaces,  as  fre- 
quently met  with  in  complex  cavity  outlines,  this  may  be  removed 
by  the  following  method :  When  cavity  is  thoroughly  packed  with 
wet  cotton,  stretch  a  piece  of  rubber  dam  over  the  matrix,  cotton 
and  all,  and  thoroughly  burnish  the  entire  outline.  If  ''spring" 
still  persists,  remove  the  matrix  and  anneal,  and  then  repeat  the 
method  when  it  will  be  found  that  the  fault  has  been  removed. 

Selection  of  Porcelain.  The  selection  of  that  portion  of  the  in- 
lay which  replaces  dentine  and  that  which  replaces  enamel  should 
be  attended  to  before  the  process  of  building  begins.  The  part 
replacing  dentine  should  be  of  foundation  body  coarsely  ground 
and  of  a  yellow  color  in  all  vital  cases.  In  devital  cases  this  shade 
may  be  darkened  by  the  addition  of  the  brown  shade,  and  in.  vital 
teeth  for  young  patients,  particularly  if  the  cavity  is  shallow,  or 
on  a  distal  surface,  the  addition  of  white  powder  is  of  advantage 
to  lighten  the  shade  of  yellow. 

The  enamel  shades  may  be  decided  upon  after  a  careful  study  of 
the  shades  and  hues  found  in  each  case.  Delicate  shading  is  se- 
cured by  building  one  layer  upon  another,  thus  getting  the  benefits 
of  reflected  light.  The  deep  and  pronounced  shades  and  colors  are 
best  obtained  by  building  in  sections.  Teeth  that  are  much  of  one 
color  and  not  pronounced  in  lines  of  shades  will  be  best  represented 
by  the  layer  method,  while  teeth  that  are  decidedly  yellow  at  the 


CONSTRUCTION   AND   PLACING    OF   PORCELAIN   INLAY  309 

cervix  and  pronouncedly  blue  at  the  ineisal  edge  are  best  repre- 
sented by  building  in  sections  provided ;  the  cavity  involves  both 
regions  spoken  of  as  in  Class  Four  (proximo-incisal). 

After  the  different  sections  have  been  applied  and  brought  to  a 
hard  biscuit  fuse,  a  uniform  layer  of  neutral  color  is  applied  over 
the  whole  and  all  fully  fused. 

Applying-  the  Porcelain  to  the  Matrix.  The  foundation  body  is 
put  upon  the  porcelain  or  glass  slab  and  sufficient  distilled  water, 
or  alcohol  or  a  mixture  of  both,  added  to  make  a  stiff  paste,  stiff 
enough  to  retain  its  shape  when  taken  up  on  the  point  of  a  spatula. 

A  small  quantity  of  this  is  laid  in  the  bottom  of  the  matrix  and 
by  a  little  jolting  made  to  flow  over  the  surface.  This  jolting  is 
best  produced  by  drawing  the  edge  of  a  fine  gold  file  over  the 
tweezers  holding  the  matrix.  The  additions  should  be  continued 
until  sufficient  body  has  been  added.  Excess  moisture  is  removed 
by  repeated  jolting  and  absorbing  with  blotting  paper.  Dark  col- 
ored blotting  paper  is  used  so  as  to  detect  any  paper  fibers  Avhich 
by  accident  adhere,  which  should  be  removed.  The  addition  of 
dry  porcelain  of  the  same  color  will  take  up  the  excess  moisture, 
the  surplus  adhering  powder  being  brushed  off  with  a  small  brush. 

In  Case  the  Matrix  is  Torn,  the  opening  has  to  be  comparatively 
large  to  cause  the  porcelain  to  run  through,  unless  the  matrix  is 
damp  on  the  cavity  side  or  too  moist  a  mix  is  being  applied. 
Should  any  of  the  porcelain  flow  through,  it  can  be  removed  with 
a  dry  brush  provided  the  porcelain  has  been  rendered  quite  dry. 

Do  not  apply  a  wet  brush  to  the  cavity  side  of  the  matrix.  The 
inlay  should  now  be  placed  in  the  oven  and  fused  sufficiently  to 
produce  the  greater  part  of  the  shrinkage,  but  not  to  a  full  gloss. 
When  removed  from  the  oven  if  more  foundation  is  needed  it 
should  bo  added  and  fired  to  a  high  biscuit. 

The  Enamel  in  Proper  Shades  is  now  added,  either  in  layers  or 
sections,  and  again  fired  to  a  high  biscuit.  The  inlay  should  then 
be  tried  into  the  cavity  for  bulk  and  contour.  If  not  correct  more 
enamel  is  added.  When  the  contour  suits,  the  inlay  is  replaced  in 
the  oven  and  fired  to  a  full  glaze.  The  skill  necessary  to  reproduce 
the  colors  of  the  teeth  comes  with  practice  and  the  longer  one  en- 
gages in  this  work  the  more  often  Avill  the  results  please  the  oper- 
ator, 

Technic  of  Fusing-  Porcelain.  The  furnace  should  be  first  heated 
up  to  a  Ijriglit  ]■(',(]  and  licl'l  lliere  for  n   minute  or  Uvo,  to  thor- 


310  OPERATIVE    DENTISTRY 

oughly  warm  the  fire  clay  entirely  through,  and  then  the  lever  re- 
turned to  the  first  button  to  maintain  a  v-'arm  oven. 

When  ready  to  fuse,  the  furnace  is  completely  shut  off  provided 
the  oven  shows  any  redness.  Never  put  an  inlay  mix  into  a  hot 
oven,  as  it  causes  too  rapid  evaporation  of  the  moisture,  producing 
checks  and  an  extremely  friable  porcelain. 

When  the  inlay  is  in  position  in  the  oven  the  lever  is  put  on  the 
second  or  third  button  and  advanced  only  when  the  needle  of  the 
milliamperemeter  ceases  to  advance.  The  heat  should  be  increased 
gradually  and  when  it  has  reached  the  desired  degree  immediately 
shut  off.  Each  furnace  has  a  way  peculiar  to  itself  and  each  oper- 
ator should  learn  the  time  for  perfect  results. 

Grinding-  to  Contour.  After  the  final  fusing  the  inlay  should  be 
tried  in  and  ground  to  contour  and  articulation  on  the  incisal  or 
occlusal  surface  before  removing  the  matrix. 

To  Remove  the  Matrix.  Drop  the  inlay  and  the  matrix  in  alco- 
hol or  water,  then  remove  and  peel  the  matrix  from  the  inlay,  draw- 
ing from  the  margins  all  around  first,  then  from  the  body  of  the 
filling.     This  procedure  prevents  chipping  at  the  margins. 

Etching-  the  Cavity  Side  of  Inlay.  When  the  matrix  has  been 
removed  the  inlay  shoiQd  be  embedded,  contour  surface  down,  into 
a  sheet  of  pink  base  plate  wax.  With  a  warm  spatula  it  is  sealed 
entirely  around,  being  sure  to  cover  the  edges  of  the  inlay  on  the 
cavity  side  for  a  short  distance,  say  one-half  millimeter.  This 
leaves  the  cavity  side  exposed,  upon  which  is  applied  hydrofluoric 
acid.  This  is  applied  by  dipping  a  stick  in  the  wax  bottle  in  which 
the  acid  is  delivered,  and  painting  the  inlay  with  a  small  quantity 
of  the  acid.  Two  minutes  will  generally  be  sufficient  to  thoroughly 
etch  the  surface. 

Toilet  of  Inlay.  The  inlay  should  be  flooded  with  water,  re- 
moved from  the  wax  and  placed  in  boiling  water  for  a  few  minutes 
and  then  given  a  chloroform  bath,  and  dried  with  warm  air  while 
laying  on  spunk  or  blotting  paper,  and  should  not  be  again  con- 
tacted with  the  hands  on  the  cavity  side. 

Toilet  of  Cavity.  The  cavity  should  be  rendered  dry.  All  in- 
lays, and  particularly  the  large  ones,  are  best  set  with  white  ce- 
ment with  the  faintest  tinge  of  cream.  The  attempt  to  match  the 
color  of  tooth  substance  with  the  cement  is  an  error  as  the  pigment 
in  the  cement  increases  the  shadow  line  which  is  objectionable. 
Use  a  white  cement  mixed  to  the  consistency  of  greatest  adhesive- 
ness yet  thin  enough  to  flow  from  between  inlay  and  cavity  walls 


CONSTRUCTIOX  AND  PLACING  OF  PORCELAIN  INLAY       311 

with  light  pressure.  This  will  be  about  the  consistency  of  thin 
cream.  The  cement  should  be  thoroughly  and  rapidly  spatulated 
and  when  the  ''stick"  is  felt  under  the  spatula  it  should  be  ap- 
plied to  the  cavity  and  the  surface  of  the  inlay  which  is  immediate- 
ly placed.  Use  a  non-corrosive  spatula,  preferably  bone  or  agate. 
Apply  to  the  cavity  with  a  flattened  orangewood  stick.  Press  in- 
lay to  position  with  a  stick  of  orangewood  using  gentle  pressure, 
gently  tapping  the  end  of  stick  with  the  knuckle  of  the  forefinger, 
or  blows  of  equally  cushioned  nature. 

In  labial  and  buccal  fillings  (Class  Five)  the  inlay  should  re- 
ceive gentle  pressure  for  five  or  ten  minutes.  In  proximal  (Classes 
Three  and  Four)  the  filling  should  be  gently  wedged  against  the 
proximating  tooth  or  tightly  ligatured  to  position  and  so  left  for 
some  hours. 

The  Finishing-  should  be  left  till  another  sitting.  If  the  building 
has  been  "svell  done  there  will  be  little  to  do.  All  overhanging  mar- 
gins should  be  dressed  doAvn  with  fine  stones  and  disks  and  the 
surface  polished  with  small  Arkansas  stones,  using  a  light  hand 
and  keeping  the  stones  well  watered. 


APPENDIX 

As  a  suggestion  to  those  Avho  use  this  book  as  a  text  in  college 
teaching,  the  author  submits  the  following  courses  based  on  the 
subject  matter  of  the  foregoing  chapters  and  illustrations.  Herein 
are  also  shoAvn  the  author's  selection  of  instruments  for  doing  the 
■work  and  Dr.  Rathbun's  "dentech"  to  take  the  place  of  the  pa- 
tients. 

While  carrying  out  this  course  the  freshman  completes  the  first 
seventeen  chapters.  During  the  second  year  the  student  hurriedly 
reviews  the  first  seventeen  chapters  and  completes  the  remainder  of 
the  book.  The  courses  in  both  the  first  and  second  years  are  quiz 
courses.  The  third  year  students  review  the  book  entirely  w^ith 
the  teacher  giving  lectures  elaborating  on  each  subject  by  adding 
personal  ideas  to  give  individuality  to  the  course.  The  fourth 
year  is  devoted  |o  a  study  of  the  subject  as  presented  by  other  writ- 
ers, each  member  of  the  class  writing  papers  for  the  consideration 
of  his  fellow-classmen,  who  should  be  allowed  to  discuss  the  papers 
presented. 

Operative  and  Dental  Anatomy  Technic  Courses 

FRESHMAN  YEAR. 

First  Semester. 

(1)  Fourteen  plaster  tooth  carvings,  three  times  Black's  measure- 
ments. 

Second  Semester. 

(2)  Fourteen  bone  tooth  carvings,  average  measurements. 

(3)  Six  bone  tooth  carvings  from  models  of  extracted  teeth. 

(4)  Nine  cavities  as  assigned  in  technic  block,  finished  March  1st. 

(5)  Twenty-four  cavities  as  assigned  in  fourteen  plaster  teeth. 
finished  May  1st.     (See  Figs.  13  and  14.) 

JUNIOR   YEAR. 

First  Semester. 

(6)  Fill  nine  cavities  in  technic  block. 

(7)  Mount  bone  carvings  and  natural  teeth  on  "dentcch."  (See 
Fig.  177.) 

(8)  Fill  natural  teeth  as  per  following  list. 

A.     Second  lower  molar.     Occlusal.     Class  One  cavity.     Expose 

313 


314 


OPERATIVE   DENTISTRY 


Fig.  170. — Excavators,  group  one.     Chisels  for  securing  outline  form. 


APPENDIX 


315 


Fig.    171.— Kxcavators,  group  two.     Si)Oons  for  removing  softened  dentine. 


316 


OPERATIVE   DENTISTRY 


Fig.    172. — Excavators,   group   three.      Enamel   hatchets   for   completing  outline   form  and  ] 

flattening  dentine  walls.  ■ 


APPENDIX 


317 


•"ig.  173.      Kxcavators,  group  four.     Instrumenls  for  cutting  point  angles  and  sharpening 

base  line  angles. 


318 


OPERATIVE   DENTISTRY 


Fig.    174. — Excavators,  group   five.      Hatchets   and   hoes   for  cutting  ascending  line  angles   and 

completing  retention  form. 


APPENDIX 


319 


Fig.    175.— Kxcavators,  group  six.     Gingival   marginal   trimmers.      InMrumcits   for  «:hnT)intr  an.l 

finishing  gingival  walls.  ' 


320 


OPERATIVE   DENTISTRY 


I 


Fig.    176-B. 

Figs.  176,  A  and  B. — Gold  building  pluggers.. 
Numbers  one  to  seven  inclusive  are  for  building 
foil  gold.  These  instruments  have  the  same  sized 
serrations  and  are  made  in  conformity  with  the 
principles  taught  in  Chapters  XIX  and  XX.  In- 
struments numbers  eight  to  twelve  inclusive  are 
for  building  fiber  gold.  These  five  instruments 
have  serrations  specially  adapted  for  use  on  this 
form  of  gold.  In  changing  from  foil  builders  to 
fiber  gold  builders  or  vice  versa  the  surface  of 
the  gold  should  be  gone  entirely  over,  before  add- 
ing the  differently  prepared  gold,  with  the  instru- 
ment with  which  the  operator  expects  to  condense 
the    new    gold. 


Fig. 
176-^. 


APPENDIX 


321 


Fig.  177. — Dr.  Rathhun's  dc-ntech  with  teeth  in  position  ready  tor  practice  work.  This 
appliance  may  be  used  either  on  the  bencli  or  head  rest  of  any  operating  chair.  The  author 
advises  the  advanced  worlt  with  this  on  the  dental  chair  to  familiarize  the  student  with 
positions. 


322 


OPERATIVE    DENTISTRY 


pulp.    Devitalize.    Remove  pulp.    Fill  pulp  canals.    Fill  cavity  vs/'ith 
silver  cast  inlay. 

B.  Upper  lateral.    Lingual  pit.     Class  One.     Open  and  treat  for 
putrescence.     Fill  pulp  canal.     Fill  cavity  with  amalgam. 

C.  Second  lower  bicuspid.    Occlusal  pit.    Class  One  cavity.    Open 


Fig.  178. — This  shows  a  student  who  has  kept  his  appointment  with  his  patient,  "Mr. 
Dentech."  The  student  is  required  to  keep  an  appointment  book  with  this  dummy  patient 
the  same  as  though  the  mouth  to  be  worked  on  was  animate. 


and  treat  for  putrescence.     Fill  pulp  canal.     Fill  cavity  with  tin. 

D.  Upper  central.  Distal.  Class  Three  cavity.  Expose  pulp. 
Devitalize.    Fill  pulp  canal.    Fill  cavity  with  cement. 

E.  First  lower  molar.  Mesial.  Class  Two  cavity.  Devitalize. 
Remove  pulp.  Fill  pulp  canal.  Fill  cavity  with  tin,  restoring  con- 
tact. 

F.  First  superior  molar.  Mesial.  Class  Two  cavity.  Devitalize. 
Fill  pulp  canals.  Fill  with  amalgam  restoring  the  contour  and  con- 
tact. 


APPENDIX 


323 


G.  Second  superior  molar.  Class  One  cavity.  Central  pit  rather 
large.  Prepare  so  as  not  to  injure  the  pulp  in  vital  case.  Fill  with 
amalgam. 

H.     First  and  second  superior  bicuspids.     Mesial  cavities.     Class 


Fig.    179. — Forceps   made   after  the   patterns   of   the  author.      The   middle   and    right  hand 
pairs  are  spoon  beak  forceps,  hollow  ground  and  should  be  kept  reasonably  sharp  by  grinding. 


Two.  Expo.se  pulps.  Use  pressure  anesthesia.  Remove  pulps.  Fill 
pulp  canals  of  both.    Fill  both  cavities  with  tin. 

I.  First  inferior  molar.  T'lass  Five.  Prepare  cavity  and  fill  with 
amalgam  without  injury  to  the  pulp. 

./.     Admitted  to  infirmary  practice. 


324 


OPERATIVE   DENTISTRY 


Second  Semester.  \ 

(9)     Twenty-four  cavities  in  carved  bone  teeth  mounted  on  "den-  i 

tech, ' '  duplicating  those  in  plaster  teeth  of  the  freshman  year.     Cut  ] 

and  fill  in  the  order  listed,  completing  each  filling  before  cutting  the  \ 

next  cavity.  \ 


Fig.  180. — Forceps  made  after  the  patterns  of  the  author.     The  right  hand  pair  is  a  combination 
of  cow  liorn  and  hawk  bill  beak. 


INDEX 


A 
Abrasion: 

causes   not    clear,    96 

incisal,    97 

mechanical,   195 
Abscess: 

alveolar,  acute,  179 

alveolar,  chronic,  224 
Absorbents,  187,  194 
Absorbent    cotton,    use    of,    175 
Access  form,  defined,  31 

importance  of,  31 

surgical  for,  31 
Access  form  for: 

class   two, 

first  method,  58 
second  method,   59 
third   method,   59 

class   three,    72 

inlays,    99 

class    two,    102 
class    three,    105 

silicate,    150 
Affected   dentine,    29 
Alloy, 

ageing    of,    140 

annealing    of,    141 
Alveolus,    opening    mouth    of,    234 
Amalgam: 

cavity   preparation    for,    141 

contraction   of,   140 

cutting  from  the  margins  for,  144 

defined,    139 

edge    strength    of,    140 

expansion   of,   140 

expressing   mercury  from,   143 

flat    seats   for,    141 

flow   of,  140 

history,    139 

making    the    filling,    144 

making  the  mix,   142 

matrix,   removal   of,  114 

matrix,    use    of,    141 

maximum    strength    of,    140 


Amalgam — Cont  'd 
objections   to,   139 
polishing   of,    145 
properties   of,   139 
proportion   of   alloy   and  mercury, 

142 
reception   of,    129 
trimming   the   filling   of,   144 
Anesthesia: 

conductive,    285 

infiltration,   282 

intra-alveolar,    201 

local    and   regional,    275,    292 

pressure,   for   pulp,   213,   214 

pulp,   212 

sensitive    dentine,    202 

sensitive      dentine,       general   for, 

202 
surface,    282 
Angles,  avoided  in  outline,   34 

avoided  in   outline,   class   two,   61 
line,   class   two,  62 
Angle    restoration: 

conditions   demanding,   class  four, 

78 
plans  of,  class  four,  78 
plan  one,  class  four,  85 
plan  two,  class  four,  87 

indications   for,    88 
plan  three,   class  four,   89 

indications    for,    88 
plan    four,    class    four,    90 
Appendix,   313,   324 
Arsenic  tri oxide: 

caution   in   use    of,   217 
combination,    215 
poisoning    from,    217 
retainer,    216,    217, 
technic   in,   use   of,    216 
amalgam  as  a,  216 
cement    as   a,    217 
cotton    as   a,   217 
stopping  as  a,   217 
soreness  from,  217 
time   of   aiijtlication   of,   217 


325 


326 


INDEX 


Bevel   angle,   base   of,   28 

defined,    27 
Broacli,    cotton    carrying,    226 
Burnishing   cohesive   gold,   137 

0 

Calculus: 
salivary: 

composition   of,   181 

removal   of,   183 
serumal : 

appearance  of,  183 

deposited,    182 

distinguished  from,   184 

removal   of,   184 
Canal  point,  size   of,  227 
Canal,  filling,  pulp: 
chlora-percha    as,    227 
general,  225-228 
gutta-percha   as,  227 
immediate,    215,    218 
material  for,   225 
most    popular,    227 
necessity  of,  225 
objective  point  in,  225 
perfect,    225 
ready  for,   225 
Caries: 

progressive   stage   of,   207 
rapid,   indications  of,   167,   195 
Carious    dentine: 
in  large  decays,  44 
in  large   proximal   cavities,  44 
predisposing  causes,   class  one,  48 

class  two,  58 
removal    of     remaining,      defined, 
44 
Cavities: 

axial    surface,    21 

base  of,  24 

buccal  and  lingual  surfaces,  55 

cavo-surface   angle,   defined,   27 

for   fused    porcelain,   295 
class  one,  defined,  22 
class  two,   defined,   22 

early    detection    essential,    58 
non-vital,   67 


Cavities — Cont  'd 

class   three,    defined,   22 

form   of,   72 

management   of,   72 
class   four,    78-92 

defined,   22 

inlay,   63 
class   five,    93-95 

defined,    22 

prevention    of,    93 

tendency   to   spread,   93 
class   six,  96,   97 

cause  of,   96 

defined,   96 

early  restoration  in,   97 

line  angles  in,  25 

occlusal  surfaces,   97 
complex,    21 

distal    superior    cuspids,    91 
divisions    as    to    manipulation,    22 
groups    of,    21 
how    named,    21 
increased    outline   in,    dangers   of. 

-  37 
laying   of   outline,   37 
mesio-disto-occlusal,       non-vital, 

68 
mesio-disto-occlusal,    vital,    68 
point   angles   in,  25 
proximal,    21 
simple,   21 

stress  from  within,  38 
toilet   of,  45-47 
Cavity  nomenclature,  21-28 
necessity  of,   21 
names,   how    derived,    21 
Cavity   preparation: 
completed,    defined,    29 
general   consideration   of,  30 
gold   inlay,    98-111 
modification   of  form,  29 
order  of  procedure  in,   29 
porcelain  inlay,   296-305 
Cements: 

amalgam,   and,    170 
cavity  preparation   for,   146 
cement,   int.   v.   defined,   148 
cement,   n.    defined,   148 
cement,  t.  v.   defined,  148 


INDEX 


327 


Cements — Cont  'd 

eementatiou,  ii.  do&ied,  148 

gold,   and,  1G9 

porcelain,   and,   171 

retainer   of   arsenic,    217 

varieties   of,    146 
Cementum,  exposure  of,  196 
Children 's     teeth,    management     of, 
229-233 

cavities,  class  one,  in,  230 

cavities,    class   two,    in,    230 

cavities,  class  three,  in,  231 

cavity   preparation   in,    230 

early    attention    imperative,    229 

exposed  pulp,  in,  231 

extension   for   prevention   in,   230 

extension   for   resistance   in,   230 

filling  materials   in,  230 

first    difficulty  in,   229 

first   visit   of   child,   229 

inter-proximal    grinding    in,    231 

root  filling  in,   232 
Chip  blower,  use  of,   176 
Chloroform,    202 
Clamp: 

cervical,  use   of,   194 

methods  of   applying,   191,   194 
Cocaine: 

for   sensitive    dentine,    277 

local  anesthesia,  with,  277 
Combination  fillings, 

cement  and  amalgam,   170 

cement   and   porcelain,    171 

defined,   169 

gold  and  cement,   170 

gold,    cohesive    and     non-cohesive 
170 

gold   and   platinum,    170 

gold    and   tin,    169 

object  of,   169 

silicate   and   amalgam,    172 

silicate   cement   and      fused      por- 
celain,  171 

silicate  and  gold,  171 
Contact   point,   proper,   32 

build  of,   amalgam,  144 

class  six,   97 

condensing  of,   132 

position   of,    132 


Convenience    form,   42-43 
abuse   of,  42 
class  one,  50 
class  two,  63,  60 
class   three,    77 
defined,   42 

distal   superior   cuspid,    92 
inlays,   99 

maximum   required,   42 
minimum   required,   42 
porcelain   inlays,    296 
previous   separation   lessening,    42 
silicate,    154 
sparingly  used,  42 
suitable   instruments  for,  42 

D 

Dentech,    321 
Deposits,    180 

food  as  related  to,   181 

habits    as    to,    181 

kinds,   upon   the   teeth,   180 

mouths  most  subject  to,  181 

salivary,    prevention    of,    182 

time   of,   181 
Disinfection     and     pulp    protection, 

46 
Disks  and     strips,   are     in  use     of, 

46 
Dryness,    187 

importance    of,    187 

neglect  of,   187 

E 

Electric  lamps,  use   of,  176 
Enamel: 

defined,  97 

edge,  97 

malformed,    305 

margin,   27 

plane    of,   45 
Enamel    walls,   45 

axial,   surface   pit,   56 

class   one,    50 

class   two,   63,   67 

class   three,   77 

inlay,   class   two,    104 

inlay,  class  four,  109 


328 


INDEX 


Enamel  walls — Cont'd 
inlay,    porcelain,    297 
silicate,    154 
Examination   of  moutlis: 
care   in,    175 

instruments    needed   in,    175 
light  liand  in,  174 
when   completed,    176 
Exclusion  of  moisture,  186 
as  a  time  saver,  189 
better  view   of  the   cavity,   188 
decalcification    detected,    189 
for  proper  canal  treatment,   188 
for   sterilization,    188 
methods  of,   186 
pain  decreased  by,  189 
Explorer,    use    of,    175 
External  enamel   line,    defined,   27 
Extensions    gingivally: 
buccal,   class   one,   56 
buccal,   class  two,   60 
Extension   for   prevention : 
approaching  the  gum,  56 
buccal  pits,   56 
defined,  35 
esthetic    reasons,    74 
Extraction    of     teeth,      permanent, 
233-268 
care   in,   263 
forces  used  in,   234 
general    consideration    of,    233 
hemorrhage    following,    267,    268 
movements    in,    234 
positions  in,  234 
position  of   arms  in,   240 
position  of  hands  in  240 
position  of   operator  for  inferior, 

238 
position   of  operator  for  superior, 

235 
resistance   of   patient   in,   243 
rules  for, 

inferior  bicuspids,   253 
superior   bicuspids,    249 
inferior    cuspids,    249 
superior  cuspids,  245 
inferior  incisors,  245 
superior   incisors,   244 
inferior  molars,   259 
superior  molars,   256 


Extraction  of  teeth: 
rules  for — Cont'd. 

third,  inferior  molar,  262 
third,   superior  molar,  262 
temporary  teeth,  269-274 

early  extraction,  evil  results  of, 

269 
first   molar,    related   to,    269 
first   molar,     time    of     eruption, 
reasons    for,    269 


F 


Feldspar,   formula    of,   293 
Finishing  cohesive  gold  filling,  137 

abrasives   in,   138 

burnishing    in,    137 

gingival  excess  in,  137 

knife,   in,   138 

strips,   in,    138 
Floss   silk,  waxed,  use   of,   176,   186 


G 


Gingival  Angles,   class  four,   83 
Gingival    outline, 

class   two,   61,   65 

class  three,   73 

class  five,  94 
Gold: 

annealing  of,   124 

application   of,    127 

bridging  of,  125 

building  of  class  five,  136 

building   of   class  six,   136 

cement  and,   169 

cohesion  of,   125 

cohesive    physical   properties,    123 

condensation,   secondary,   137 

condensing   of,   127 

covering  of  pulpal  wall,  with,  131 

hand  pressure  in  use   of,   127 

last   portions   of,    class   two,    133 

layers    of,    135 

objectionable   qualities,   of,   123 

order  of  stepping,  129 
buccal   cavities,    129 
class  two,  130 
irregular   outline,   129 
occlusal  cavities,  129 


INDEX 


329 


Gold— Cont  'd 

platinum   and,   170 
preparation    of,    126 
specific   gravity   of,   125 
starting    a    filling, 

class   one,   129 

class   two,   129 

class  three,  133 

class   four,   135 
tin    and,    169 
use   of,  in   class   five,   95 
welding   of,   123 
Gum  massage,  185 
Gutta-percha,    16i 
base    plate,    164 
canal  points  of,   165 
filling  root  canals  with,   164 
filling  with,   164 
preparation  of  filling,   164 
separation    with,    165 
temporary  stopping  of,  165 


H 

Hand   pressure,   cohesive   gold,   12  S 
Health  of  patient,  207 
Hydrogen  dioxide,  185 
Hj-peremia : 

active,    177,    206 

passive,    178 

stages   of,    206 
Hypersensitive       dentine,       defined, 
195 

caustic   potassa   in,   200 

chloroform    in,    202 

cold  air  in,  199 

dessication    of,    198 

destroying   agents   in,   199 

electric   current   in,    199 

formaldehyde   in,   200 

moisture,   heat   and   cold   in,   199 

nitrous  oxide  in,  202 

novocain,   201 

oil  of  cloves  in,  201 

phenol   in,    200 

potassium   bromide   in,   202 

rapid  breathing  in,  203 

sharp   instruments   in,   203 

silver   nitrate   in,   200 

Bomnoforme    in,   202 


Hypersensitive  dentine — Cont  'd 
treatment   of,   195-203 
zinc    chloride    in,    200 


Incisal   abrasion,   class   six,   97 
Incisal  angle: 

class  three,  filling  of,  87 
class  four,  78 

class   four,    direction    of,    81 
class  four,   to   assist   the,   86 
Incisal    edge,    porcelain    inlay,    304 
Incisal   line    angle,    class   three,    75 
Incisal   outline: 
class   three,    74 
class  four,  plan  one,   87 
class   five,    94 
Infected  dentine,  29 
Inlays : 

beveling    of    cavo-surface    angles, 

100 
carving    the    wax,    114 
defined,   98 
finishing    the,    122 
gold  used,   in,   121 
heating  the  gold,  for,   120 
history   of,    112 
hole   leading  to  model,   121 
indications   for,    98 
investing,  pattern  of,   119 
line  of  approach,  for,  100 
making  pattern,  for,   113,   119 
making  the  cast,   of,   120 
materials   for,   98 
matrix  for,    119 
not   indicated,   98 
object  of,  112 

occlusal  restoration,  with,  118 
pin  for,   116 

placing   spruce   wire   for,   115 
porcelain,     construction    of,      306- 
311 
applying    of,    309 
etching   of,    310 
finishing    of,    310 
grinding  of,  310 
matrix   for,    306 
pushing  tcchnic   of,   310 
selection   of,   308 
toilet    of,   310 


530 


INDEX 


Inlays — Cont  'd 

retention  form   for,   51 

retention      temporarily      removed, 

51 
retention  form   of   pattern,    115 
saturating  the  model,  120 
setting,    122 

sponge  gold   as  pattern,   119 
sweating    the    contour,    118,    119 
temperature   of  the  model,  120 
toilet  for,   100 
undercuts,    filling    of,    113 
wax  pattern,  for,   113 
Instruments,  17-20 
angles  in,  18 
bin-angles  in,  18 
bur,   19 
care  of,  20 
chisel, 

defined,    18 

edge,   18 

use   of,   18 
class  name,   II 
contra   angles  in,   18 
cuts   of,   314,   324 
dental  engine,  use  of,  19 
exrjavators,    17 
few   in   sight,   174 
formula   names,   for,   18 
gingival    marginal    trimmer,    18 
hatchets,   defined,  18 
hoes,    defined,   18 
how   named,    17 
nomenclature,   for,    17-20 
plugger,    point    serrated,    19,    125, 
126 

amalgam,    143 

rotating   the,    126 

size   of,   126 
rights  and  lefts,  17 
sharpening   of,    19 
spoon,  use  of,  18 
sub-class   name,   17 
sub-order  name,   17 
test  for   sharpness,   20 
triple-angles  in,   18 
Instrumentation,    lingual    pit,    57 


K 


Kaolin,  formula  of,  293 


Labial  outline: 

class   three,   74 

class  four,  plan   one,  rule  for,   8G 

class  four,  plan  three,   90 
Length    of   sitting    (children),    230 
Ligature,   192 

caution  in  use  of,  192 

cutting  ends  of,   193 

how  made,  192 

knot  in,  193 

removal  of,   193 

Wedelstaedt  tie,   193 
Lime    salts   in    solution,      precipita- 
tion of,   181 
Line  angles,    (see  Cavity), 

axio-labial,   class   three,   76 

axio-lingual,   class   three,   76 

gingivo-axial,    77 
Linen,   174 
Lingual  approach: 

advised,  135 

class   three,    cohesive   gold,    135 

inlay  illustrated,   105 
Lingual   outline : 

class  three,  75 

class  four,  plan  one,  87 

lower   incisors,    87 
Local  anesthesia: 

anatomy,  relatfd  to,  277 

cocaine  in,   277 

defined,   275 

horizontal   injection   in,   285 

infiltration  in,  283 

intra-alveolar  in,   285 

novocain,   doses  of,   279 

novocain  in,   277 

pericemental    injection    in,    286 

perpendicular   injection   in,   285 

preparing    solution   for,    280 

Einger's    solution   for,    281 

suprarenin,    doses   of,   280 

suprarenin   in,   280 

uses  in  dentistry,  276 


M 


Mallet  force: 
alone,  128 
automatic,   128 


INDEX 


331 


Mallet  force — Cont'd 

hand,   128 

power,   128 

rule  of,   128 
Marginal  bevel: 

angle  of,  45 

defined,   27 

depth   of,  45 

necessity  of,  27 
Matrix: 

annealing   of,   306 

applying   porcelain   to,    309 

material,  for,  306 

methods   of  forming,   306 

porcelain  inlay,  306 

removal    of,    amalgam,    144 

removal   from   porcelain,   310 

taking  the  spring  out  of,  308 

thickness   of,   306 

torn,    309 

use  of,  class  two,  gold,   133 

use  of,  in  silicate  filling,  162 

use   of,   with    amalgam,    141 
Mouth  mirror,  use  of,  175 

N 

Novocain: 

sensitive    dentine,    201 

tablets,    care    cf,    281 
Nitrous  oxide,  202 

O 

Objects  in  filling  teeth,   29,  96 
Occlusal  defects,  48 
Occlusal  outline: 

class   two,   66 

class  five,   94 
Operative  technic  courses,  313,  322, 

323,   324 
Order   of   procedure: 

cavity,  29 

for    inlays,    99 
Outline    form: 

buccal   pits,   55 

class  one,  48 

class  two,  59,  65 

class  three,  73 

class  five,   303 


Outline  form — Cont'd 

curving   to   the    axial,    class   four, 
86 

defined,  34 

distal   superior   cuspids,    91 

for   silicate,   151 

inlays, 

class  one,  101 
class  two,  103 
class  three,  105 

large  class  one,  52 

lingual   pits,   55 

porcelain   inlays,   296 

rule  one  of,  34 

rule  two  of,  34 

rule  three   of,   34 

rule  four  of,  34 

rule  five  of~  34 

rule  six  of,  34 

rule  seven  of,  34 

rule   eight   of,   34 

rule  nine   of,   35 

rule  ten   of,  35 

step   omitted  in   class  two,   59 
Over   dessication,   71 
Oxychloride   of  zinc,   146 
Oxyphosphate   of  copper,   147 
Oxyphosphate   of  zinc,      146 

manipulation   of,    147 

spatulation  of,  147 


Pain,   dental: 

alleviations  of,   177 

cold,    causes,    177 

divisions    of,    177 

foreign    substances,    causes,    178 

patents  in,  175 

pericemental      diseases,      causing, 
179 

symptoms,    aggravated,    177 

treatment  for,  177,  178,  179 
Passive  hyperemia  of  pulp,  178 
Pins: 

placing  for  inlay,  116 

soldered  to   matrix,   116 

Tungston,   116 
Planes   of   :i  tooth: 

bucco-lingual,    28 


332 


INDEX 


Planes  of  a  tooth — Cont'd 

horizontal,   28 

mesio-distal,   28 
Porcelain: 

advantages   of,  294 

basal  body,   294 

biscuit   fuse,   294 

build   of   layers,   294 

cavo-surface    angle   for,    295 

cement   line   in,   301 

composition   of,    293 

contra-indications   for,   295 

dental,  fused,  293-295 

disadvantages  of,  294 

double  step  in,  302 

enamel  body,   294 

fine  grinding  of,  294 

flux,   amount  of,   294 

foundation  body,   294 

high  fusing,   293,   294 

indications   for,    295 

lingual   approach,   class  three  for, 
300 

low   fusing,   293 

methods   of   fusing,    293 

pigments  in,  293 

proximal   approach  for,  301 

shrinkage  in,  294 

size   of  mass,   24 

spheroiding    of,    294 
Potassium    bromide,    202 
Preventive   dentistry,   180 
Primary   decay,    location   of,      class 

three,    72 
Prophylactic  treatment,  oral,  180 

brushing,    technie    of,    186 

importance  of,  180 

instructions    to    patients   in,    186 

oral     hygiene,    children,   229 
Proximal  Space,  restoration  of,  31 
Pulp: 

canals, 

air  in,  227 

bent,   226 

putrescent,   219 

small,  management  of,  225 

chamber,    cleaning   of,    228 

chief  idiosyncrasy  of,  204 

devitalization, 
causes  for,   211 
agents  for,   212 


Pulp : 

■  devitalization — Cont  'd 
anesthetization  for,  212 
arsenic    trioxide,    for,    215 
bacteria  as  related  to,   211 
care   exercised  in,   214 
determining     the      method      of, 

212 
high  pressure  for,  213 
methods   of,   212 
technie    of,   213 

exposed,  class  one,  53 

exposure,  dangers  in,  class  two,  65 

exposure    feared,    class    one,    52 

infected   with   bacteria,   206 

involved,  class  five,  95 

lesions   of,   177 

normal,   204 

partially  devitalized,  218 

peripheral    nerve    irritation,    212 

preservers,  209 

protection,    204-210 
gutta   percha   in,   210 
in   class   two,    66 
in    deep    seated   cavities,   207 
indications  for,  205 
materials  used  in,   207 

putrescence,   219-224 
animal  fats  in,  221 
autogenous,    symptoms   of,   222 
autogenous,    treatment    of,    222 
classes  of,  219 
closed,  symptoms  of,  222 
closed,  treatment  of,  222 
complicated,    symptoms    of,    223 
complicated,  treatment  of,  223 
defined,    219 

open,  symptoms  of,  220 
open,  treatment  of,  220 
treatment   of,    general,   220 

recuperative  powers  of,  204 

removal   of,   214-218 

canal    dressing    following,    215 
canal  filling   following,    215 
discolorations    following,    215 
hemorrhage   following,   215 
pains   following,   215 

sensations   are   conveyed   to,   195 

stimuli,   abnormal,   211 

stimuli,    normal,    211 

traumatic  injuries  to,  211 


INDEX 


333 


Pus  in  apical  space,  179  " 
Putrefaction  defined,  219 
Pyorrhea    alveolaris,   IS-t 

R 

Eegional    anesthesia: 

defined,   287 

gasserian   injection   in,   288 

infra-orbital   injection   in,    290 

mental  injection  in,   290 

palatine  injection  in,  292 

pterygo-niandibular   injection     in, 
288 

spheno-maxillary  injection  in,  288 

zygomatic   injection   in,   290 
Eemoval  of  remaining  decay: 

class   one,  50 

class  two,  66 

class   three,    77 

for   cilicate,   154 

inlays,  99 
Resistance   form: 

applied  to   filling  material,   39 

buccal  pits,  55 

class   one,  49 

class  two,   62,   66 

class  three,   75 

extension  for,  defined,  38 

force   to  provide  for  in,  38 

for  porcelain  inlays,  296 

for   silicate    inlays,    151 

importance  of,  38 

inlays,    99 

class  one,  101 
class  two,  103 
class  four,  plan  one,  106 

involves  a   consideration  of,  38 
Retention    angles   for   inlays,    99 
Retention  form: 

acute  angles  required  in,  40 

buccal   pits,   56 

class  one,  49 

class  two,  62,  66 

class  three,   75 

class   four,   78-81 

class  five,  94 

flat  seats  in,  40 
inlays, 
class    one,    102 


Retention  form: 

flat  seats  in — Cont'd 
class  two,  103 
class   four,   plan   two,   107 

for  porcelain  inlays,  296 

for  silicate,   153 

little,  in  enamel,  41 

maximum   not  required,   40 

maximum   required,   40 

step  as  a  portion  of,  40 
Einger^s  solution,  281 
Rubber  dam: 

before  ai^plying,   38 

class   one,   52 

essential  in  filling  with  amalgam, 
141 

for   silicate,   154 

gingival   side   of,   191 

holes,   distance  between,   190 

holes,  location  of,  190 

holes,  size  of,  190 

invented   by,    387 

leaks   in,  46 

method  of  applying  the,  191 

number    of      teeth    isolated   with, 
191, 

objections  to  use  of,  187 

occlusal  side  of,  191 

placing   of,    191 

prevent  leakage  in,  192 

removal   of,   194 

size  and  shape   of,  190 

thickness   of,   189 

S 

Secretions,   abnormal,   oral,   196 
Separation: 

class  two  cavities,  59 

for  amalgam,  142 

gutta-percha   for,   165 

immediate,   33 

inlays,  class  two,  102 

methods   of,   32 

preliminary,   33 

soreness    resulting   from,   33 

mechanical   not   essential,   176 

use  of,  class  two,  gold,  133 
Silex,  formula  of,  293 
Silicate: 

amalgam,   and,   171 


334 


INDEX 


Silicate — Cont  'd 

applied   to   prosthetic   work,    172 

cavity  preparation   for,   150 

defined,  148 

facing  metal  fillings  with,    160 

finishing  the  filling,   162 

gold,  and,   171 

making   the   filling,   155 

making  the   mix,   159 

preparing    the    materials,    158 

proper   consistency,   159 

time  in  mixing,  160 

use   of   matrix,   162 
Silieatization,    defined,    148 
Somnoform,   202 
Sordes,   consistency  of,   183 
Sordes,  removal  of,  183,  185 
StaijQS   on  the   teeth,   183 

green   stains,   color   due   to,    183 
injury   to   teeth,   183 
removal    of,    185 
where   found,    183 
Step: 

area  included,   class  two,   61 

depth  of  class  four,  plan  two,   87 

distal   superior    cuspids,    91 

forming  of,   61 

omitted   in   class   two.   51 

technic    of      cutting,     class     four, 
plan  two,   88 

T 

Teeth: 

compared,   270 
order, 

changes   in,   271 

disregarding   of,   272 

of   eruption,   270 
Tin: 

amalgam  and,   168 

as  a  filling  material,  166 

cavity   preparation   for,    167 

discoloration,    amount    of,    166 

discoloration,   by,    166 

forms  of,   167 

gold  and,  168,   169 

history  of,   166 

in   teeth   of   children,   167 

methods   of   introduction,    167, 

therapeutic  action  of,  166 

thermal  conductivity  of,   166 


Toilet  of  cavity: 

best  accomplished  by,  45 

class    one,    51 

class  two,  67 

defined,  45 

for  porcelain  inlays,  297,   310 

for    silicate,    154 
Tooth: 

brush,  use  of,   185 

form,  restoring  of,  32 

picks,  186 

substance,   saving   of,   32 
Tubuli,  contents  of,  195 

W 

Wall: 

axial, 

class  two,  62 

class  three,   77 

defined,   23 

for  porcelain,  class  one,  298 

for   porcelain,    class   three,    299 
buccal,   class   two,   62 
distal   superior    cuspid,    91,    92 
freshly    cut,    88 
gingival,    defined,    23 
gingival,   class  two,   66 
gingival,    class   three,    77 
gingival,    class    three,    inlay,    105 
inside,    defined,   24 
labial,  77 
lingual,    77 
lingual,  axial,  62 
lingual,    class   two,    92 
occlusal,    class   five,   inlay,    110 
outside,    defined,    22 
pulpal,  class  two,   62 
pulpal,   defined,   22 
sub-pulpal,    defined,   23 
weakened    enamel,    38 
Wide   enamel  margin,  indicated,   46 


Zinc: 

chloride   of,   200 
oxychlorate   of,   146 
oxyphosphate   of,   146 
sulphate  of,  147 


D29 
1916 


RK501 

Davis 

Essentials  of  operative  dentistry. 


